Cyclone such as for use in a surface cleaning apparatus

ABSTRACT

A cyclone comprises a cyclone chamber having an air inlet, an air outlet, a screen upstream of the air outlet, a longitudinal axis, a first end wall, a second end wall and a sidewall, the air inlet having a cross sectional area in a plane transverse to a direction of airflow through the air inlet and the screen having an inner end spaced longitudinally inwardly from the air outlet and having a cross-sectional area transverse to the cyclone axis that is less than the cross sectional area of the air inlet.

FIELD

This specification relates to cyclones having improved efficiency. In apreferred embodiment, a surface cleaning apparatus, such as a vacuumcleaner, is provided which utilizes one or more improved cyclones.

INTRODUCTION

The following is not an admission that anything discussed below is partof the prior art or part of the common general knowledge of a personskilled in the art.

Various types of surface cleaning apparatus are known. Typically, anupright vacuum cleaner includes an upper section, including an airtreatment member such as one or more cyclones and/or filters, drivinglymounted to a surface cleaning head. An up flow conduit is typicallyprovided between the surface cleaning head and the upper section. Insome such vacuum cleaners, a spine, casing or backbone extends betweenthe surface cleaning head and the upper section for supporting the airtreatment member. The suction motor may be provided in the upper sectionor in the surface cleaning head.

Currently, many vacuum cleaners utilize one or more cyclonic stages toremove particulate matter from an air stream. Typically, the cycloneswhich are utilized comprise a cyclone chamber defined by an upper wallwhich is planar, a lower wall which is planar and the side wall which iscylindrical. Typically, an air inlet is provided at one end and an airoutlet is provided at the opposed end. Alternate cyclone designs havebeen disclosed. For example, U.S. Pat. No. 8,250,702 discloses a cyclonehaving an air inlet and an air outlet at one end and a dirt outlet atthe opposed end. The opposed end with the dirt outlet has a roundedtransition member extending between the end wall facing the air outletand the side wall of the cyclone chamber.

SUMMARY

This summary is intended to introduce the reader to the more detaileddescription that follows and not to limit or define any claimed or asyet unclaimed invention. One or more inventions may reside in anycombination or sub-combination of the elements or process stepsdisclosed in any part of this document including its claims and figures.

According to a broad aspect, a cyclone, such as may be used in a vacuumcleaner or other surface cleaning apparatus, is provided. Turbulence oreddy currents which develop in a cyclone chamber may reduce theefficiency of the cyclone chamber. For example, the eddy currents mayresult in mixing of different layers of air and accordingly, air whichhas had particulate matter removed therefrom could be mixed with airwhich still contains particulate matter. In addition, the back pressurecreated by the passage of air through a cyclone chamber may be increasedby turbulence and eddy currents which are created in a cyclone chamber.The cleaning efficiency of a surface cleaning apparatus, such as avacuum cleaner, depends upon the velocity of air flow at the air inlet.All other factors remaining the same, an increase in the rate of airflow at the dirty air inlet of a vacuum cleaner will increase thecleaning efficiency of the vacuum cleaner. Accordingly, reducing theback pressure through a cyclone chamber may increase the cleaningefficiency of a vacuum cleaner.

In one embodiment, a cyclone chamber is provided wherein the portion ofthe cyclone chamber at the cyclone air inlet is configured to have ashape that is at least preferably proximate the shape of the air exitingthe cyclone air inlet and entering the cyclone chamber. For example, thecyclone air inlet may be provided at a position where the sidewall of acyclone chamber meets an end wall of the cyclone chamber. Typically, thesidewall and end wall of cyclone chambers meet at a 90° angle. Inaccordance with this embodiment, the juncture of the sidewall and theend wall are preferably configured to at least approximate a portion ofthe shape of the air inlet adjacent this juncture. For example, thejuncture of the end wall and side wall of the cyclone chamber may beangled and, preferably, rounded and, most preferably, radiused so as tohave the same shape as the outlet end of the cyclone chamber inlet.Accordingly, the air which travels through the cyclone air inlet intothe cyclone chamber may maintain its same cross-sectional shape as itenters the cyclone chamber. The airstream may expand increasing itscross-sectional area as it travels through the cyclone chamber. However,the air will have a smoother transition to the cyclonic flow in thecyclone chamber than if the juncture of the sidewall and end walls is ata 90° angle. An advantage of this design is that the back pressurecreated by the cyclone chamber may be reduced and turbulence or eddycurrents may be reduced or eliminated by smoothing the transition fromthe air inlet to the cyclone chamber at the air inlet end.

In some embodiments, the air inlet may be at the same end as the airoutlet. In such a case, a vortex finder may extend inwardly into thecyclone chamber from the same end wall at which the cyclone air inlet isprovided. In such a case, it is preferred that the vortex finder ispositioned such that the air entering the cyclone chamber from theoutlet end of the cyclone air inlet is spaced from the vortex finder.The distance between the sidewall and the vortex finder is preferablygreater than the diameter of the outlet end of the cyclone air inlet.Accordingly, as air enters the cyclone chamber from the cyclone airinlet, it will be spaced from the vortex finder. In accordance with thisembodiment, a portion of the end wall will extend from a position thatis equivalent to the diameter of the outlet end of the air inlet and thevortex finder. This portion of the end wall may be of variousconfigurations. For example, it may be rounded or angled. Preferably,this portion of the end wall is flat.

It will be appreciated by a person skilled in the art that the spacingof the vortex finder from the sidewall disclosed herein need not beutilized with the contouring of the juncture of the end wall and sidewall at the cyclone air inlet, but may be used by itself, or incombination with any other feature disclosed herein.

Alternately or in addition, the juncture of the sidewall of the vortexfinder and the end wall of the cyclone chamber may also be rounded. Anadvantage of this design is that the back pressure through the cyclonechamber may be reduced. It will be appreciated that the juncture of thesidewall of the vortex finder and the end wall of the cyclone chambermay be angled, but is preferably rounded and, more preferably has aradius that is proximate the radius of the juncture of the sidewall andend wall at the cyclone air inlet. It will be appreciated by a personskilled in the art that any of the features of the rounding of thejuncture of the vortex finder and the end wall of the cyclone chamberdiscussed herein need not be utilized with the contouring of thejuncture of the end wall and side wall at the cyclone air inlet, but maybe used by itself, or in combination with any other feature disclosedherein.

In some embodiments, the air inlet and the air outlet of the cyclonechamber may be at the same end. An insert may be provided on the opposedwall of the cyclone chamber and extend into the cyclone chamber. Forexample, the insert may be aligned with the vortex finder but at theopposed wall. In such a case, the sidewall of the insert and the opposedend wall may meet at the juncture which is shaped similar to that of anyof the junctures disclosed herein. For example, the juncture of thesidewall of the insert in the opposed end wall of the cyclone chambermay be angled and is preferably rounded and, more preferably, has aradius which is proximate to that of the radius of the juncture of thesidewall and the end wall at the air inlet. It will be appreciated by aperson skilled in the art that any of the features of the shaping of thejuncture of the sidewall and the opposed end wall need not be utilizedwith the contouring of the juncture of the end wall and side wall at thecyclone air inlet, but may be used by itself, or in combination with anyother feature disclosed herein.

In another embodiment, a vacuum cleaner may have a pre-motor filter. Aheader may be provided upstream and/or downstream of the pre-motorfilter. For example, the cyclone air outlet may extend to a headerupstream of the pre-motor filter. The header enables the air exiting theair outlet to extend across the entire pre-motor filter upstream surfacethereby allowing the entire pre-motor upstream surface to be used as afiltration mechanism. A header may be provided on the downstream side ofthe pre-motor filter. The header allows air to exit the pre-motor filterfrom all portions of the downstream side of the pre-motor filter and tobe directed towards, e.g. as central outlet so as to convey the air to asuction motor inlet. The walls of the upstream and/or downstream headermay be configured to reduce back pressure through such a pre-motorfilter housing. For example, the juncture of the cyclone air outlet andthe wall of the pre-motor filter header facing the upstream side of thepre-motor filter may be shaped similar to that of any of the juncturesdisclosed herein and may be angled or radiused. Alternately, or inaddition, the juncture of the wall of the pre-motor filter header facingthe upstream side of the pre-motor filter where it meets a sidewall ofthe pre-motor filter housing may be shaped similar to that of any of thejunctures disclosed herein and may be angled or radiused. The wall ofthe header opposed to the upstream surface of the pre-motor filter mayitself be continuously curved or angled as it extends outwardly to thesidewall of the filter housing and need not be parallel to the pre-motorfilter. In a particularly preferred embodiment, the air outlet of thecyclone chamber may be trumpet shaped (e.g., flared) and accordingly thetransition to the wall opposed to the upstream end of the pre-motorfilter may be smooth (i.e., there may be no discontinuities). It will beappreciated that such a design may permit the air exiting the cyclonechamber to transition with less turbulence into the header therebyreducing the back pressure of the air travelling through the upstreamheader of a pre-motor filter.

Alternately, or in addition, the juncture of the downstream header airoutlet and the wall of the pre-motor filter header facing the downstreamside of the pre-motor filter may be shaped similar to that of any of thejunctures disclosed herein and may be angled or radiused. Alternately,or in addition, the juncture of the wall of the pre-motor filter headerfacing the downstream side of the pre-motor filter where it meets asidewall of the pre-motor filter housing may be shaped similar to thatof any of the junctures disclosed herein and may be angled or radiused.The wall of the header opposed to the downstream surface of thepre-motor filter may itself be continuously curved or angled as itextends outwardly to the sidewall of the filter housing and need not beparallel to the pre-motor filter. In a particularly preferredembodiment, the air outlet of the downstream header may be trumpetshaped (e.g., flared) and accordingly the transition from the wallopposed to the downstream end of the pre-motor filter to the headeroutlet may be smooth (i.e., there may be no discontinuities). It will beappreciated that such a design may permit the air exiting the pre-motorfilter to transition with less turbulence into the downstream headeroutlet thereby reducing the back pressure of the air travelling throughthe downstream header of a pre-motor filter.

It will be appreciated by a person skilled in the art that any of thefeatures relating to the shaping of the upstream and/or downstreampre-motor filter header need not be utilized with the contouring of thejuncture of the end wall and side wall at the cyclone air inlet, but maybe used by itself, or in combination with any other feature disclosedherein.

In accordance with another embodiment, the pre-motor filter may besupported on a plurality of ribs which are provided on the end wall ofthe downstream header facing the pre-motor filter. The ribs arepreferably configured so as to impart a flow of air in the samedirection as the direction of rotating fan blade of the suction motor.Accordingly, the ribs may be rounded and extend towards a center of thesuction motor air inlet.

In a preferred embodiment, the suction motor inlet may be trumpet shaped(e.g. flared) and the ribs may extend along a portion of the trumpetshaped section of the air inlet to the suction motor. In such a case,the upstream side of the ribs preferably is at the same height so as toprovide a flat surface to support the pre-motor filter. Accordingly, theheight of the ribs may increase as the ribs extend into the trumpetshaped portion of the suction motor inlet. It will be appreciated by aperson skilled in the art that any of the features of the ribs of thesuction motor inlet need not be utilized with the contouring of thejuncture of the end wall and side wall at the cyclone air inlet, but maybe used by itself, or in combination with any other feature disclosedherein.

In accordance with another embodiment, the vortex finder may be providedwith a screen. The screen may surround a portion of the sidewall of thevortex finder and extend further into the cyclone chamber further thanthe vortex finder. Alternately, the screen may be mounted on theinnermost end of the vortex finder and extend further into the cyclonechamber. Preferably, the inner end of the screen (i.e. the end of thescreen that is inner most of the cyclone chamber) has a diameter that isless than the diameter of the vortex finder and/or a diameter that isless than the diameter of the outlet end of the cyclone air inlet. Thescreen may be conical in shape and may extend from the innermost end ofthe screen to a position adjacent the sidewall of a vortex finder or itmay abut the innermost end of the vortex finder. Alternately, the screenmay be cylindrical or any other shape. Preferably, the outermost end ofthe screen (e.g. the screen adjacent the inlet end of the vortex finder)has a diameter approximate the diameter of the vortex finder. Anadvantage of this design is that the distance between the screen and thesidewall of the cyclone chamber is increased and provides additionalroom to allow the air travelling in the cyclone chamber to reversedirection and enter the vortex finder. The additional room reduces, forexample, the likelihood of the treated air mixing with the air enteringthe cyclone chamber and transferring particulate matter from the airentering the cyclone chamber to the treated air.

It will be appreciated by a person skilled in the art that any of thefeatures of the shaping of the screen discussed herein may not beutilized with the contouring of the juncture of the end wall and sidewall at the cyclone air inlet, but may be used by itself, or incombination with any other feature disclosed herein.

In accordance with another embodiment, the cyclone chamber may have asidewall outlet. For example, a dirt collection chamber may be providedadjacent one side of or may surround all of the cyclone chamber. Thedirt outlet may be provided at an upper end of the sidewall and comprisea gap between all or a portion of the sidewall and the end wall of thecyclone chamber and preferably a portion of the sidewall and the endwall of the cyclone chamber (e.g., a slot provided in the sidewall atthe end wall of the cyclone chamber). The slot may be of various shapes.For example, the walls of the slot may be rounded and one end of theslot may be taller than the other, preferably the downstream side in thedirection of rotation of air in a cyclone chamber.

Alternately, or in addition, a barrier wall may be provided spaced fromthe dirt outlet and accordingly extend between the dirt outlet and thesidewall of the dirt collection chamber facing the dirt outlet. Thebarrier wall may be parallel to the cyclone chamber wall or thedownstream end of the barrier wall may be spaced further from thecyclone chamber wall than the upstream end of the barrier wall. Thebarrier wall may be affixed to an end wall of the dirt collectionchamber, a sidewall of the dirt collection chamber and/or the sidewallof the cyclone chamber. If the barrier wall is connected to the sidewallof the cyclone chamber, the barrier wall is preferably connected to thesidewall of the dirt collection chamber upstream of the dirt outlet. Theheight of the barrier wall may be the same as the dirt outlet but it maybe shorter or longer. In addition, the height may vary in the downstreamdirection.

It will be appreciated by a person skilled in the art that any of thefeatures of the dirt outlet and/or barrier wall discussed here need notbe utilized with the contouring of the juncture of the end wall and sidewall at the cyclone air inlet, but may be used by itself, or incombination with any other feature disclosed herein.

In another embodiment, the suction motor housing may have an inner wallwhich is scalloped. For example, the end wall of the motor housingfacing the suction motor may be scalloped. Alternately, the sidewallgenerally parallel to the cyclone motor axis may be scalloped.Preferably, the sidewall which is scalloped is opposed to a sidewall airoutlet from the suction motor housing. An advantage of this design isthat the scalloped shape reflects noise back towards the suction motorthereby reducing the sound of the suction motor of a vacuum cleaner. Thereduction in noise can also result in a reduction in the back pressurethrough the vacuum cleaner, and, accordingly, an increase in thecleaning efficiency of the vacuum cleaner. It will be appreciated by aperson skilled in the art that any of the features of the shaping of thesuction motor housing discussed herein may not be utilized with thecontouring of the juncture of the end wall and side wall at the cycloneair inlet, but may be used by itself, or in combination with any otherfeature disclosed herein.

The vacuum cleaner which uses the cyclone and/or pre-motor filterhousing and/or suction motor housing that is disclosed herein may beprovided with a turbo brush. For example, this vacuum cleaner may havean above-floor cleaning wand and a turbo brush may be attachablethereto. Due to the reduced back pressure which may be achievedutilizing one of more of the features disclosed herein, a turbo brushmay be used while still obtaining good cleaning efficiency. Accordingly,by reducing the back pressure through the cyclone chamber and/orpre-motor filter housing and/or motor housing, the saving in thereduction of the back pressure may be utilized to power or assist inpowering a turbo brush thereby providing good cleaning efficiency whileenabling a turbo brush to be utilized.

In accordance with another embodiment, the suction motor housing mayincorporate a sound absorbing material or structure. For example, asound absorbing material may be provided in the suction motor housingwhich is constructed from a plurality of different sound absorbingmaterials. For example, a sound absorbing sheet may be produced usingsmall pieces of different sound absorbing material such as polyurethane,silicon and the like. Each material will typically absorb sound in aparticular frequency range. The use of a combination of differentmaterials will allow a single piece of sound absorbing material toabsorb a greater frequency range of sounds. Further, the sheet may bemade utilizing different sized pieces of the different materials.Alternately, or in addition, a sound shield may be provided which has aplurality of layers with different sized openings. For example, aplurality of screens having different sized openings may be spaced apartand may have foam provided therebetween. The different sized openingswill restrict the transmission of sound therethrough in a different way.Preferably, the screens are made of one or more of a metallic material,glass or carbon fiber. The combination enables a vacuum cleaner to havea quieter sound by reducing the transmission of sound through themultiple layers without unduly impeding the flow of air therethrough. Itwill be appreciated by a person skilled in the art that any of thefeatures of the sound absorbing material or shield disclose herein maynot be utilized with the contouring of the juncture of the end wall andside wall at the cyclone air inlet, but may be used by itself, or incombination with any other feature disclosed herein.

In one embodiment, there is provided a cyclone comprising a cyclonechamber having an air inlet, an air outlet, a screen upstream of the airoutlet, a longitudinal axis, a first end wall, a second end wall and asidewall. The air inlet may have a cross sectional area in a planetransverse to a direction of airflow through the air inlet. The screenmay have an inner end spaced longitudinally inwardly from the air outletand may have a cross-sectional area transverse to the cyclone axis thatis less than the cross sectional area of the air inlet.

In some embodiments, the cross sectional area of the inner end of thescreen may be 60-90% the cross sectional area of the air inlet.

In some embodiments, the cross sectional area of the inner end of thescreen may be 70-80% the cross sectional area of the air inlet.

In some embodiments, the screen may be tapered outwardly towards to airoutlet.

In some embodiments, the screen may have an outer end at the air outletand the air outlet may have a diameter proximate that of the outer endof the screen.

In some embodiments, the screen may have an outer end at the air outletthat is recessed radially inwardly of the air outlet.

In some embodiments, the air outlet may comprise a vortex finder. Theair inlet and the vortex finder may be provided at the first end wall.The vortex finder may extend into the cyclone chamber a first distanceand the air inlet may have an inner end that extends into the cyclonechamber a distance less than the first distance.

In some embodiments, the air outlet may comprise a vortex finder. Theair inlet and the vortex finder may be provided at the first end walland a portion of the first end wall may extend between the air inlet andthe vortex finder and the portion may be flat.

In some embodiments, the air inlet may be provided at a first junctureof the sidewall and the first end wall. The first juncture downstream ofthe air inlet may be configured to at least approximate a portion of ashape of the air inlet that is adjacent the first juncture.

In some embodiments, the first juncture may extend at an angle to thewalls between which it is positioned.

In some embodiments, at the first juncture may be rounded.

In some embodiments, the air outlet may comprise a vortex finder havingan upstream end and a downstream end and the downstream end may be widerthan the upstream end.

In some embodiments, the vortex finder may be flared in a downstreamdirection.

In one embodiment, there is provided a surface cleaning apparatuscomprising the cyclone, an air flow path extending from a dirty airinlet to a clean air outlet and including a suction motor and thecyclone, a pre-motor filter having an outer perimeter and positioned inthe air flow path between the cyclone and the suction motor and at leastone of an upstream air plenum that is positioned upstream of thepre-motor filter and a downstream air plenum that is positioneddownstream of the pre-motor filter. At least one of the upstream and thedownstream air plenum may comprise an end wall spaced from the pre-motorfilter and comprising a first portion having an air flow port and asecond portion proximate the outer perimeter of the pre-motor filter.The first portion and the second portion may meet at a first juncturethat extends at an angle to the first portion and the second portion.

In some embodiments, the first portion may extend generally laterallyand may have an outer end and an inner end proximate the air flow portand the outer end may be closer to the pre-motor filter then the innerend.

In some embodiments, the first juncture may be rounded.

In some embodiments, the air outlet may comprise a vortex finder. Thesurface cleaning apparatus may comprise the upstream air plenum and theair flow port may comprise an air inlet port that is aligned with thevortex finder.

In some embodiments, the vortex finder may extend to the air inlet port.

In some embodiments, the vortex finder and the end wall may meet at asecond juncture. The second juncture may extend at an angle to both thevortex finder and the end wall.

In some embodiments, the second juncture may be rounded.

It will be appreciated by a person skilled in the art that a surfacecleaning apparatus may embody any one or more of the features containedherein and that the features may be used in any particular combinationor sub-combination.

DRAWINGS

The drawings included herewith are for illustrating various examples ofarticles, methods, and apparatuses of the teaching of the presentspecification and are not intended to limit the scope of what is taughtin any way.

In the drawings:

FIG. 1 is a perspective view of a surface cleaning apparatus in astorage position;

FIG. 2 is a rear perspective view of the surface cleaning apparatus ofFIG. 1;

FIG. 3 is a perspective view of the surface cleaning apparatus of FIG. 1in a floor cleaning position;

FIG. 4 is a cross sectional perspective view taken along line F4-F4 inFIG. 1;

FIG. 5 is cross sectional view taken along line F5-F5 in FIG. 2;

FIG. 6 is a perspective view of the surface cleaning apparatus of FIG. 1in a cleaning configuration;

FIG. 7 is a perspective view of the surface cleaning apparatus of FIG. 1in another cleaning configuration;

FIG. 8 is a perspective view of the surface cleaning apparatus of FIG. 1in another cleaning configuration;

FIG. 9 is a perspective view of the surface cleaning apparatus of FIG. 1in another cleaning configuration;

FIG. 10 is a perspective view of the surface cleaning apparatus of FIG.1 in another cleaning configuration;

FIG. 11 is a perspective view of the surface cleaning apparatus of FIG.1 in another cleaning configuration;

FIG. 12 is a perspective view of the surface cleaning apparatus of FIG.1 in another cleaning configuration;

FIG. 13 is a perspective view of the surface cleaning apparatus of FIG.1 in another cleaning configuration;

FIG. 14 is a perspective view of the surface cleaning apparatus of FIG.1 in another cleaning configuration;

FIG. 15 is a perspective view of the surface cleaning apparatus of FIG.1 in another cleaning configuration;

FIG. 16 is a perspective view of the surface cleaning apparatus of FIG.1 in another cleaning configuration;

FIG. 17 is a partially exploded perspective view of the surface cleaningapparatus of FIG. 1 wherein the cyclone bin assembly is removed foremptying;

FIG. 18 is a partially exploded perspective view of the surface cleaningapparatus of FIG. 1 wherein the cyclone bin assembly is removed foremptying and the pre-motor filers are removed for cleaning;

FIG. 19 is a perspective view of a cyclone bin assembly from the surfacecleaning apparatus of FIG. 1;

FIG. 20 is a sectional view of the cyclone bin assembly of FIG. 19,taken along line F20-F20 in FIG. 19;

FIG. 21 is a sectional view of the cyclone bin assembly of FIG. 19,taken along line F21-F21 in FIG. 19

FIG. 22 is a sectional view of the cyclone bin assembly of FIG. 19,taken along line F22-F22 in FIG. 19;

FIG. 23 is a sectional view of the cyclone bin assembly of FIG. 19,taken along line F23-F23 in FIG. 19;

FIG. 24 is a perspective view of the cyclone bin assembly of FIG. 19with the bottom door in an open position;

FIG. 25 is a cross sectional view of another embodiment of a cyclone binassembly;

FIG. 26 is a cross sectional view of another embodiment of a cyclone binassembly;

FIG. 27 is a cross sectional view of another embodiment of a cyclone binassembly;

FIG. 28 is a cross sectional view of another embodiment of a cyclone binassembly;

FIG. 29 is a cross sectional view of another embodiment of a cyclone binassembly;

FIG. 30 is a cross sectional view of another embodiment of a cyclone binassembly;

FIG. 31 is a cross sectional view of another embodiment of a cyclone binassembly;

FIG. 32 is a cross sectional view of another embodiment of a cyclone binassembly;

FIG. 33 is a cross sectional view of another embodiment of a cyclone binassembly;

FIG. 34 is a cross sectional view of another embodiment of a cyclone binassembly;

FIG. 35 is a cross sectional view of another embodiment of a cyclone binassembly;

FIG. 36 is a cross sectional view of another embodiment of a cyclone binassembly;

FIG. 37 is a cross sectional view of another embodiment of a cyclone binassembly;

FIG. 38 is a schematic representation of another embodiment of a cyclonebin assembly;

FIG. 39 is a schematic representation of another embodiment of a cyclonebin assembly;

FIG. 40 is a schematic representation of another embodiment of a cyclonebin assembly;

FIG. 41 is a schematic representation of another embodiment of a cyclonebin assembly;

FIG. 42 is a schematic representation of another embodiment of a cyclonebin assembly;

FIG. 43 is a schematic representation of another embodiment of a cyclonebin assembly;

FIG. 44 is a perspective schematic representation of another embodimentof a cyclone bin assembly;

FIG. 45 is a perspective schematic representation of another embodimentof a cyclone bin assembly;

FIG. 46 is a perspective schematic representation of another embodimentof a cyclone bin assembly;

FIG. 47 is a perspective schematic representation of another embodimentof a cyclone bin assembly;

FIG. 48 is a perspective schematic representation of another embodimentof a cyclone bin assembly;

FIG. 49 is an exploded perspective schematic representation of anotherembodiment of a cyclone bin assembly;

FIG. 50 is an exploded perspective schematic representation of anotherembodiment of a cyclone bin assembly;

FIG. 51 is a perspective schematic representation of another embodimentof a cyclone bin assembly;

FIG. 52 is a perspective schematic representation of another embodimentof a cyclone bin assembly;

FIG. 53 is a schematic representation of another embodiment of a cyclonebin assembly;

FIG. 54 is a schematic representation of another embodiment of a cyclonebin assembly;

FIG. 55 is a perspective schematic representation of another embodimentof a cyclone bin assembly;

FIG. 56 is a perspective schematic representation of another embodimentof a cyclone bin assembly;

FIG. 57 is a schematic representation of a surface cleaning unit;

FIG. 58 is a schematic representation of another embodiment of a surfacecleaning unit;

FIG. 59 is a modified version of the schematic representation of FIG.59;

FIG. 60 is a schematic representation of another embodiment of a surfacecleaning unit;

FIG. 61 is a perspective view of a the top of the suction motor housingof the surface cleaning apparatus of FIG. 1;

FIG. 62 is a top view of the top of the suction motor housing of thesurface cleaning apparatus of FIG. 61;

FIG. 63 is a perspective cut away of a suction motor housing of anotherembodiment of a surface cleaning apparatus;

FIG. 64 is a perspective cut away of a suction motor housing of anotherembodiment of a surface cleaning apparatus;

FIG. 65 is a perspective cut away of a suction motor housing of anotherembodiment of a surface cleaning apparatus;

FIG. 66 is a perspective view of a suction motor housing of anotherembodiment of a surface cleaning apparatus;

FIG. 67 is a cross sectional view of the portion of the surface cleaningapparatus of FIG. 66; and,

FIG. 68 is a schematic representation of an embodiment of a soundabsorbing material.

DETAILED DESCRIPTION

Various apparatuses or processes will be described below to provide anexample of an embodiment of each claimed invention. No embodimentdescribed below limits any claimed invention and any claimed inventionmay cover processes or apparatuses that differ from those describedbelow. The claimed inventions are not limited to apparatuses orprocesses having all of the features of any one apparatus or processdescribed below or to features common to multiple or all of theapparatuses described below. It is possible that an apparatus or processdescribed below is not an embodiment of any claimed invention. Anyinvention disclosed in an apparatus or process described below that isnot claimed in this document may be the subject matter of anotherprotective instrument, for example, a continuing patent application, andthe applicants, inventors or owners do not intend to abandon, disclaimor dedicate to the public any such invention by its disclosure in thisdocument.

General Description of an Upright Vacuum Cleaner

Referring to FIGS. 1-3, a first embodiment of a surface cleaningapparatus 1 is shown. In the embodiment shown, the surface cleaningapparatus is an upright vacuum cleaner. In alternate embodiments, thesurface cleaning apparatus may be another suitable type of surfacecleaning apparatus, such as a canister type vacuum cleaner, and handvacuum cleaner, a stick vac, a wet-dry type vacuum cleaner or a carpetextractor.

In the illustrated example, the surface cleaning apparatus 1 includes anupper portion or support structure 2 that is movably and drivinglyconnected to a surface cleaning head 3. A surface cleaning unit 4 ismounted on the upper portion 2. The surface cleaning apparatus 1 alsohas at least one dirty air inlet 5, at least one clean air outlet 6, andan air flow path or passage extending therebetween. In the illustratedexample, the air flow path includes at least one flexible air flowconduit member (such as a hose 7 or other flexible conduit).Alternatively, the air flow path may be formed from rigid members.

At least one suction motor and at least one air treatment member arepositioned in the air flow path to separate dirt and other debris fromthe airflow. The suction motor and the air treatment member may beprovided in the upper portion and/or the surface cleaning head of anupright surface cleaning apparatus. Preferably, the suction motor andthe air treatment member are provided in a removable surface cleaningunit. The air treatment member may be any suitable air treatment member,including, for example, one or more cyclones, filters, and bags, andpreferably the at least one air treatment member is provided upstreamfrom the suction motor. Preferably, as exemplified in FIG. 4, thesurface cleaning unit includes both the suction motor 8, in a motorhousing 12 and an air treatment member in form of a cyclone bin assembly9. The motor housing can include at least one removable or openable door13 which may allow a user to access the interior of the motor housing12, for example to access the motor 8, a filter or any other componentwithin the housing 12. The cyclone bin assembly 9 includes a cyclonechamber 10 and a dirt collection chamber 11.

Optionally, the surface cleaning unit 4 may be a portable surfacecleaning unit and may be detachable from the upper portion (FIG. 5). Insuch embodiments, the surface cleaning unit 4 may be connected to theupper portion 2 by a mount apparatus 14 that allows the surface cleaningunit 4 to be detached from the upper section 2. It will be appreciatedthat a portable surface cleaning unit 4 could be carried by a hand of auser, a shoulder strap or the like and could be in the form of a pod orother portable surface cleaning apparatus. All such surface cleaningapparatus are referred to herein as a hand carriable surface cleaningapparatus.

In the embodiment shown, the surface cleaning head 3 includes the dirtyair inlet 5 in the form of a slot or opening 15 (FIG. 4) formed in agenerally downward facing surface of the surface cleaning head 3. Fromthe dirty air inlet 5, the air flow path extends through the surfacecleaning head 3, and through an up flow conduit 16 (FIG. 2) in the upperportion 2 to the surface cleaning unit 4. In the illustrated example,the clean air outlet 6 is provided in the front of the surface cleaningunit 4, and is configured to direct the clear air in a generally lateraldirection, toward the front of the apparatus 1.

A handle 17 is provided on the upper portion 2 to allow a user tomanipulate the surface cleaning apparatus 1. Referring to FIGS. 1 and 3,the upper portion extends along an upper axis 18 and is moveably mountedto the surface cleaning head 3. In the illustrated example, the upperportion 2 is pivotally mounted to the surface cleaning head via a pivotjoint 19. The pivot joint 19 may be any suitable pivot joint. In thisembodiment, the upper portion 2 is movable, relative to the surfacecleaning head 3, between a storage position (FIG. 1), and a use or floorcleaning position (FIG. 3). In the floor cleaning position the upperportion 2 may be inclined relative to the surface being cleaned, and anangle 19 between a plane 20 parallel to the surface and the upper axis18 may be between about 20 and about 85°.

Alternatively, or in addition to being pivotally coupled to the surfacecleaning head, the upper portion may also be rotatably mounted to thesurface cleaning head. In this configuration, the upper portion, and thesurface cleaning unit supported thereon, may be rotatable about theupper axis. In this configuration, rotation of the upper portion aboutthe upper axis may help steer the surface cleaning head across the floor(or other surface being cleaned). It will be appreciated that theforgoing discussion is exemplary and that an upright vacuum cleaner mayuse a surface cleaning head and upper portion of any design and they maybe moveably connected together by any means known in the art.

Handle/Cleaning Wand Construction

In accordance with one aspect of the teachings described herein, whichmay be used in combination with any one or more other aspects, the airflow path between the surface cleaning head 3 and the surface cleaningunit 4 includes a bendable hollow conduit or wand member 100, which maybe used in combination with a flexible hose portion 7. Preferably, thehose 7 is extensible and more preferably is elastically or resilientlyextensible.

Referring to FIG. 2, the wand member 100 includes an upper wand portion101 and a lower wand portion 102. The upper and lower wand portions 101,102 are connected to each other via a connection, e.g., a hinge 103member, which allows relative movement between the upper and lower wandportions 102, 103. Optionally, the hinge member 103 can be configured toform part of the air flow path and to provide fluid communicationbetween the upper and lower wand portions 101, 102, as well as provide apivoting, mechanical linkage. For example, upper and lower wand portions101, 102 may be moveably connected to each other by providing a pivotjoin that permits the upper and lower wand portions 101, 102 to beconnected in air flow communication or by each wand portion havingprojections that are pivotally connected to each other and with aflexible hose to provide the air flow communication between the wandportions. Alternatively, the air flow path can be external to the hinge.The handle 17 is provided toward the top of the upper portion 2 and isattached to the upper or downstream end of the upper wand portion 101.In the illustrated embodiment, the handle 17 includes a hand gripportion 21 that is configured to be grasped by a user. The hinge member103 can be locked in a straight configuration (FIG. 9) and can beunlocked to allow the upper wand portion 101 to pivot relative to thelower wand member 102 (FIG. 10).

In the illustrated example, the upper and lower wand portions 101, 102and the handle 17 are hollow tube-like conduit members that form part ofthe air flow path and can carry at least some of the weight of thesurface cleaning apparatus 4. The wand 100 is also configured totransfer driving and steering forces between the handle 17 and thesurface cleaning head 3.

The upper and lower wand portions 101, 102 may be made of any suitablematerial that can withstand the weight of the surface cleaning apparatus4 and the driving and steering forces, including, for example, plastic,metal and the like. Optionally, upper and lower wand portions 101, 102may be formed from the same material. Alternatively, they may be formedfrom different materials.

Referring to FIG. 9 the distance 104 between the surface cleaning head 3and the upper end of the handle 17 defines an upper portion height.Preferably, the upper portion height 104 can be selected so that thehandle 17 is positioned so to be grasped by users of varying heights.The upper portion height 104 may be between, for example, about 35inches and about 60 inches, and preferably is between about 40 inchesand about 50 inches. In the illustrated example, the upper portionheight 104 is between about 41 inches and about 45 inches.

The upper wand portion 101 defines an upper wand length 105 and thelower wand portion 102 defines a lower wand length 106. The upper andlower wand lengths 105, 106 may be the same, or may be different.Preferably, each of the upper and lower wand lengths 105, 106 arebetween about 15% and about 80% of the upper portion height 104.Altering the relative lengths of the upper and lower wand portions maychange the position of the hinge 103 relative to the surface cleaninghead 3.

In one aspect of the teachings described herein, which may be used incombination with any one or more other aspects, the upright vacuumcleaner 1 may be operable in a variety different functionalconfigurations or operating modes. The versatility of operating indifferent operating modes may be achieved by permitting the surfacecleaning unit to be detachable from the upper portion. Alternatively, orin addition, further versatility may be achieved by permitting portionsof the vacuum cleaner to be detachable from each other at a plurality oflocations in the upper portion, and re-connectable to each other in avariety of combinations and configurations.

In the example illustrated, mounting the surface cleaning unit 4 on theupper portion 2 increases the weight of the upper portion 2 and canaffect the maneuverability and ease of use of the surface cleaningapparatus. With the surface cleaning unit 4 attached, the vacuum cleaner1 may be operated like a traditional upright style vacuum cleaner, asillustrated in FIGS. 1-3.

Alternatively, in some cleaning situations the user may preferablydetach the surface cleaning unit 4 from the upper portion 2 and chooseto carry the surface cleaning unit 4 (e.g. by hand or by a strap)separately from the upper portion 2, while still using the upper portion2 to drivingly maneuver the surface cleaning head 3. When the surfacecleaning unit 4 is detached, a user may more easily maneuver the surfacecleaning head 3 around or under obstacles, like furniture and stairs.

To enable the vacuum suction generated by the surface cleaning unit 4 toreach the surface cleaning head 3 when the surface cleaning unit 4 isdetached from the support structure 2, the airflow connection betweenthe surface cleaning head 3 and the cleaning unit 4 is preferably atleast partially formed by a flexible conduit, such as the flexible hose7. The use of a flexible conduit allows a user to detach the surfacecleaning unit 4 and maintain a flow connection between the portablesurface cleaning unit 4 and the surface cleaning head 3 without havingto reconfigure or reconnect any portions of the airflow conduit 16 (FIG.6).

Referring to FIG. 6, when the surface cleaning apparatus 1 is in use, auser may detach the surface cleaning unit 4 from the upper portion 2without interrupting the airflow communication between the cleaning unit4 and the surface cleaning head 3. This allows a user to selectivelydetach and re-attach the cleaning unit 4 to the support structure 2during use without having to stop and reconfigure the connecting hoses 7or other portions of the airflow conduit 16.

FIGS. 6, 9 and 10 and illustrate a configuration in which the vacuumcleaner 1 can be operated with the surface cleaning unit 4 detached fromthe upper portion 2 and the air flow path between the surface cleaningunit 4 and the surface cleaning head 3 remains intact. FIG. 9 shows theupper portion 2 in a straight configuration. FIG. 10 shows the upperportion 2 in an optional bent configuration. In both configurations, thesurface cleaning head 3 is operable to clean the floor.

Alternatively, in some cleaning operations the user may wish toreconfigure portions of the air flow path to provide a surface cleaningapparatus with a desired configuration. For example, in anotherconfiguration, as exemplified in FIG. 8, the wand portion of the uppersection 2 is removed and the upstream end of the handle 17 is coupleddirectly to the surface cleaning head 3. This configuration may beuseful when cleaning stairs or other surfaces that are elevated. This isanother example of a floor or surface cleaning operating mode.

In addition to being operable to clean floors or surfaces, the vacuumcleaner may be operated in a variety of cleaning modes that do notinclude use of the surface cleaning head, and may be generally describedas above floor cleaning modes. This can generally include cleaningfurniture, walls, drapes and other objects as opposed to cleaning alarge, planar surface.

In one example of an above floor cleaning mode, as exemplified in FIG.7, the surface cleaning unit 4 can remain mounted on the upper portion2. This eliminates the need for the user to separately support theweight of the surface cleaning unit 4. In the illustrated configuration,the upstream end of the handle 17 is separated from the downstream endof the upper wand portion 100. In this configuration the upstream end 22of the handle 17 can function as the dirty air inlet for the vacuumcleaner 1. Optionally, accessory tools, such as wands, crevasse tools,turbo brushes, hoses or other devices may be coupled to the upstream end22 of the handle 17.

In another example of an above floor cleaning mode, as exemplified inFIG. 11, the surface cleaning unit 4 can remain mounted on the upperportion 2 and the upper wand portion 101 can be detached from the hinge103 to provide an extended wand for above floor cleaning. Thisconfiguration may help extend the reach of a user, as compared to theconfiguration of FIG. 7. Optionally, additional accessory tools may becoupled to the upstream end 25 of the upper wand portion 101, includingfor example a crevice tool (FIG. 15), a cleaning brush 26 (optionally anelectrically powered brush or an air driven turbo brush, see FIG. 14)and any other type of accessory including a power tool such as a sander27 (FIG. 16).

In another example of an above floor cleaning mode, as exemplified inFIG. 12, the surface cleaning unit 4 can be detached from the upperportion 2, and substantially all of the upper portion 2 can be detachedfrom the surface cleaning head 3. In this configuration, both the upperand lower wand portions 101, 102 co-operate to further extend the user'sreach, as compared to the configurations of FIGS. 7 and 11. Optionally,additional accessory tools may be coupled to the upstream end 28 of theupper portion 2.

In another example of an above floor cleaning mode, as exemplified inFIG. 13, the surface cleaning unit 4 can be detached from the upperportion 2 and the handle 17 can be detached from the upper portion 2.

Optionally, one or more auxiliary support members, including for examplea wheel and a roller, can be provided on the rear of the surfacecleaning apparatus and/or the upper portion and configured to contactthe floor (or other surface) when the upper portion is inclined orplaced close to the surface (see FIG. 10). Providing an auxiliarysupport member may help carry some of the weight of the surface cleaningunit and/or upper portion when in a generally horizontal configuration.The auxiliary support member may also help the upper portion 2 and/orsurface cleaning unit 4 to roll relatively easily over the floor when inthe horizontal position. This may help a user to more easily maneuverthe upper portion and/or surface cleaning unit under obstacles, such asa bed, cabinet or other piece of furniture. In the illustratedembodiment the auxiliary support member is a roller 30 provided on theback side of the lower wand portion 102.

Removable Cyclone

The following is a description of a removable cyclone that may be usedby itself in any surface cleaning apparatus or in any combination orsub-combination with any other feature or features disclosed herein.

Optionally, the cyclone bin assembly 9 can be detachable from the motorhousing 12. Providing a detachable cyclone bin assembly 9 may allow auser to carry the cyclone bin assembly 9 to a garbage can for emptying,without needing to carry or move the rest of the surface cleaningapparatus 1. Preferably, the cyclone bin assembly 9 can be separatedfrom the motor housing 12 while the surface cleaning unit 4 is mountedon the upper portion 2 and also when the surface cleaning unit 4 isseparated from the upper portion 2. Referring to FIG. 17, in theillustrated embodiment the cyclone bin assembly 9 is removable as aclosed module, which may help prevent dirt and debris from spilling outof the cyclone bin assembly 9 during transport.

In the illustrated embodiment, removing the cyclone bin assembly 9reveals a pre-motor filter chamber 31 that is positioned in the air flowpath between the cyclone bin assembly 9 and the suction motor 8 (seealso FIG. 4). One or more filters can be provided in the pre-motorfilter chamber 31 to filter the air exiting the cyclone bin assembly 9before it reaches the motor 8. In the illustrated example, the pre-motorfilter includes a foam filter 32 and a downstream felt layer 33positioned within the pre-motor filter chamber 31. Preferably, thefilters 32, 33 are removable (FIG. 18) to allow a user to clean and/orreplace them when they are dirty. Optionally, part or all of thesidewalls 34 of the pre-motor filter chamber or housing 31 can be atleast partially transparent so that a user can visually inspect thecondition of the filters 32, 33 without having to remove the cyclone binassembly 9.

Referring to FIG. 19, the cyclone bin assembly 9 includes an outersidewall 35 and a lid 36. Preferably, as illustrated, a bin handle 37 isprovided on the lid 36. The bin handle 37 may allow a user to carry thesurface cleaning unit 4 when it is detached from the upper portion 2,and preferably is removable from the suction motor housing 12 with thecyclone bin assembly 9 so that it can also be used to carry the cyclonebin assembly for emptying.

Referring to FIGS. 20 and 21 in the illustrated embodiment the cyclonechamber 10 extends along a cyclone axis 38 and includes a first end wall39, a second end wall 40 axially spaced apart from the first end wall 39and a generally cylindrical sidewall 41 extending between the first andsecond end walls 39, 40. Optionally, some or all of the cyclone wallscan coincide with portions of the dirt collection chamber walls, suctionmotor housing walls and/or may form portions of the outer surface ofsurface cleaning unit. Alternatively, in some examples some or all ofthe cyclone walls can be distinct from other portions of the surfacecleaning unit. In the illustrated embodiment, the cyclone chamber 10 isarranged in a generally vertical, inverted cyclone configuration.Alternatively, the cyclone chamber can be provided in anotherconfiguration, including, having at least one or both of the air inletand air outlet positioned toward the top of the cyclone chamber, or as ahorizontal or inclined cyclone.

In the illustrated embodiment, the cyclone chamber 10 includes a cycloneair inlet 42 and a cyclone air outlet 43. The cyclone chamber 10preferably also includes at least one dirt outlet 44, through which dirtand debris that is separated from the air flow can exit the cyclonechamber 10. While it is preferred that most or all of the dirt exit thecyclone chamber via the dirt outlet, some dirt may settle on the bottomend wall 40 of the cyclone chamber 10 and/or may be carried with the airexiting the cyclone chamber via the air outlet 43.

Preferably the cyclone air inlet 42 is located toward one end of thecyclone chamber 10 (the lower end in the example illustrated) and may bepositioned adjacent the corresponding cyclone chamber end wall 40.Alternatively, the cyclone air inlet 42 may be provided at anotherlocation within the cyclone chamber 10.

Referring to FIG. 20, in the illustrated embodiment the air inlet 42includes an upstream or inlet end 45, which may be coupled to the hose 7or other suitable conduit, and a downstream end 46 (FIG. 22) that isspaced apart from the upstream end 45. In the illustrated configuration,the cyclone bin assembly 9 can be removed from the surface cleaning unit4, for example for cleaning or emptying, while the hose 7 remains withthe upper portion 2. This may allow a user to remove the cyclone binassembly 9 without having to detach or decouple the hose 7.Alternatively, the downstream end of the hose 7 may be coupled to thecyclone bin assembly 9 such that the downstream end of the hose travelswith the cyclone bin assembly when it is removed.

The air inlet 42 defines an inlet axis 47 and has an inlet diameter 48(FIG. 21). The cross-sectional area of the air inlet 42 taken in a planeorthogonal to the inlet axis 47 can be referred to as thecross-sectional area or flow area of the air inlet 42. Preferably, theair inlet 42 is positioned so that air flowing out of the downstream endis travelling generally tangentially relative to, and preferablyadjacent, the sidewall 41 of the cyclone chamber 10.

The perimeter of the air inlet 42 defines a cross-sectional shape of theair inlet. The cross-sectional shape of the air inlet can be anysuitable shape. In the illustrated example the air inlet has a generallyround or circular cross-sectional shape with a diameter 48. Optionally,the diameter 48 may be between about 0.25 inches and about 5 inches ormore, preferably between about 1 inch and about 5 inches, morepreferably is between about 0.75 and 2 inches or between about 1.5inches and about 3 inches, and most preferably is about 2 to 2.5 inchesor between about 1 to 1.5 inches. Alternatively, instead of beingcircular, the cross-sectional shape of the air inlet may be anothershape, including, for example, oval, square and rectangle.

Air can exit the cyclone chamber 10 via the air outlet 43. Optionally,the cyclone air outlet may be positioned in one of the cyclone chamberend walls and, in the example illustrated, is positioned in the same endas the air inlet 42 and air inlet 42 may be positioned adjacent or atthe end wall 40. In the illustrated example, the cyclone air outlet 43comprises a vortex finder 49. In the example illustrated, thelongitudinal cyclone axis 38 is aligned with the orientation of thevortex finder. Alternatively, the cyclone air outlet 43 may be spacedapart from the cyclone air inlet 42, and may be located toward the otherend of the cyclone chamber 10.

In the illustrated embodiment the air outlet 43 is generally circular incross-sectional shape and defines an air outlet diameter 51 (FIG. 21).Optionally, the cross-sectional or flow area of the cyclone air outlet43 may be between about 50% and about 150% and between about 60%-90% andabout 70%-80% of the cross-sectional area of the cyclone air inlet 42,and preferable is generally equal to the cyclone air inlet area. In thisconfiguration, the air outlet diameter 51 may be about the same as theair inlet diameter 48.

When combined with any other embodiment, the cyclone bin assembly 9 maybe of any particular design and may use any number of cyclone chambersand dirt collection chambers. The following is a description ofexemplified features of a cyclone bin assembly any of which may be usedeither individually or in any combination or sub-combination with anyother feature disclosed herein.

Screen

The following is a description of a cyclone and a screen that may beused by itself in any surface cleaning apparatus or in any combinationor sub-combination with any other feature or features disclosed herein.

Optionally, a screen or other type of filter member may be provided onthe cyclone air 43 outlet to help prevent fluff, lint and other debrisfrom exiting via the air outlet. Referring to FIG. 21, in theillustrated example a screen 50 is positioned at the air outlet 43 andconnected to the vortex finder 49. In FIG. 21 the screen is illustratedwith mesh in place, however for clarity the mesh has been omitted fromthe other Figures. The screen 50 is generally cylindrical in theillustrated embodiment, but may be of any suitable shape in otherembodiments. Optionally, the screen 50 can be removable from the vortexfinder 49.

Optionally, the screen 50 may be sized to have a cross-section area thatis larger than, smaller than or generally equal to the air outlet 43cross-sectional area. Referring to FIG. 23, in the illustrated example,the diameter 52 of the screen 43 is less than the diameter 51 of thevortex finder 49 conduit providing the cyclone air outlet 43. In thisconfiguration, the radial surface 53 of the screen 50 is radially offsetinwardly from the surface 54 of the vortex finder 49 by an offsetdistance 55. Providing the offset gap 55 between the surfaces 53, 54 ofthe screen 50 and vortex finder 49 may help provide a relatively calmerregion (i.e. a region of reduced air flow turbulence and/or laminar airflow) within the cyclone chamber 10. It may also assist the air that hasbeen treated in the cyclone chamber to travel towards the vortex finderwhile mixing less with the air entering the cyclone chamber via the airinlet and thereby reduce the likelihood of dirt bypassing treatment inthe cyclone chamber and travelling directly to the air outlet. Providinga relatively calmer air flow region adjacent the surface 53 of thescreen 50 may help enable air to more easily flow through the screen 50and into the vortex finder 49, which may help reduce backpressure in theair flow path. Reducing back pressure may help improve the efficiency ofthe cyclone chamber and/or may help reduce power requirements forgenerating and/or maintaining a desired level of suction.

In the illustrated embodiment the screen 50 is of generally constantdiameter. Alternatively, the diameter of the screen 50 may vary alongits length. For example, the screen may be generally tapered and maynarrow toward its upper end (i.e. the end that is spaced apart from thevortex finder 49). The cross sectional area of the inner end of thescreen may be 60-90% the cross sectional area of the air inlet andpreferably is 70-80% the cross sectional area of the air inlet.

Referring to FIG. 25, another embodiment of a cyclone bin assembly 1009is shown. Cyclone bin assembly 1009 is similar to cyclone bin assembly9, and analogous elements are identified using like reference charactersindexed by 1000. In this embodiment, the screen 1050 is tapered suchthat the width 1052 at the base of the screen 1050 (adjacent the vortexfinder 1049) is greater than the width 1052 a at the upper end of thescreen 1050. In this configuration the cross-sectional area of thescreen 1050 (in a plane that is generally perpendicular to the screen50) is greater at the base of the screen 1050 than at its upper end. Theamount of taper on the screen 1050 may any suitable amount, and forexample may be selected so that the cross-sectional area at the upperend of the screen 1050 is between about 60% and 90%, between about 70%and 80% and may be about 63%-67% of the cross-sectional area of the baseof the screen 1050.

Dirt Outlet

The following is a description of a cyclone dirt outlet that may be usedby itself in any surface cleaning apparatus or in any combination orsub-combination with any other feature or features disclosed herein.

Cyclone chamber 10 may be in communication with a dirt collectionchamber by any suitable means. Preferably, as exemplified, the dirtcollection chamber 11 is exterior to cyclone chamber 10, and preferablyhas a sidewall 56 that at least partially or completely laterallysurrounds the cyclone chamber 10. At least partially nesting the cyclonechamber 10 within the dirt collection chamber 11 may help reduce theoverall size of the cyclone bin assembly. As exemplified in FIG. 20, thecyclone chamber sidewall 41 may be coincident with the sidewall 56 atone or more (e.g., three locations) around its perimeter.

In the illustrated embodiment, the dirt outlet 44 is in communicationthe cyclone chamber 10 and the dirt collection chamber 11. Optionally,the dirt outlet 44 can be axially and/or angularly spaced from thecyclone air inlet. Preferably, the cyclone dirt outlet 44 is positionedtoward the opposite end of the cyclone chamber 10 from the cyclone airinlet 42. The cyclone dirt outlet 44 may be any type of opening and maybe in communication with the dirt collection chamber to allow dirt anddebris to exit the cyclone chamber 10 and enter the dirt collectionchamber 11.

In the illustrated example, the cyclone dirt outlet 44 is in the form ofa slot bounded by the cyclone side wall 41 and the upper cyclone endwall 39, and is located toward the upper end of the cyclone chamber 10.Alternatively, in other embodiments, the dirt outlet may be of any othersuitable configuration, and may be provided at another location in thecyclone chamber, including, for example as an annular gap between thesidewall and an end wall of the cyclone chamber or an arrestor plate orother suitable member.

Referring to FIG. 21, the dirt slot 44 may be of any suitable length 57,generally measured in the axial direction, and may be between about 0.1inches and about 2 inches, or more. Optionally, the length 57 of theslot 44 may be constant along its width, or alternatively the length 57may vary along the width of the slot 44, preferably in the downstreamdirection as measured by the direction of air rotation in the cyclonechamber.

Optionally, the slot may extend around the entire perimeter of thecyclone chamber (forming a generally continuous annular gap) or mayextend around only a portion of the cyclone chamber perimeter. Forexample, the slot may subtend an angle (see angle 58 in FIG. 20) that isbetween about 30° and about 360°, and may be between about 30 and about180°, between about 45 and about 90° and between about 60 and 80°.Similarly, the slot 44 may extend around about 10% to about 80% of thecyclone chamber perimeter, and preferably may extend around about 15% toabout 40% of the cyclone chamber perimeter.

Optionally, the slot 44 may be positioned so that it is angularlyaligned with the cyclone air inlet 42, or so that an angle 60 (FIG. 20)between the air inlet and the slot 44 (measured to a center line of theslot 44) is between about 0 and about 350° or more, and may be betweenabout 90° and about 180°. In some embodiments, the slot 44 can bepositioned so that an upstream end of the slot (i.e. the end of the slotthat is upstream relative to the direction of the air circulating withinthe cyclone chamber) is between about 0° and about 350° from the airinlet, and may be between about 5° and 180° and between about 10° andabout 50° downstream from the air inlet.

Referring to FIGS. 38-43, schematic representations of alternateembodiments of a cyclone chamber and a dirt collection chamber areshown. Each embodiment is generally similar to the cyclone chamber 10and dirt collection chamber 11, and analogous elements are identifiedusing like reference characters with a unique suffix (a, b, c, etc.).Each of the schematic embodiments illustrates one example of a possibleangular arrangement between the air inlet 42, dirt outlet slot 44(represented by angle 60) and dirt outlet slots 44 of varying widths,represented by different angles 58. For clarity, in these Figuresportions of the air inlet 42 and the dirt outlet slot 44 are identifiedby cross-hatching.

Referring to FIG. 38, in this embodiment the angle 60 a between the slot44 a and the air inlet 42 a is about 45 degrees, and the dirt slot 44 asubtends an angle 58 a of about 60 degrees. In this configuration, thedirt slot 44 a is 45 degrees downstream from the air inlet 42 a and islocated in a first quadrant of the cyclone chamber sidewall (i.e. in aquadrant where the angle 60 is between about 0 degrees and about 90degrees).

Referring to FIG. 39, in this embodiment the angle 60 b between the slotoutlet 44 b and the air inlet 42 a is about 0 degrees. That is, thecentre line of the slot 44 b is generally aligned with the tangentialedge of the air inlet 42 b. In this configuration, a portion of the dirtslot 44 b (located at one end of the cyclone chamber 10 b) may overlap aportion of the air inlet 42 b (located at the other end of the cyclonechamber 10 b). In this embodiment, the angle 58 b swept by the dirt slot44 b is about 35 degrees. Also in this embodiment, portions of thecyclone chamber sidewall 41 b are integral with portions of the dirtcollection chamber sidewall 56 b, and the air inlet 42 a is at an anglerelative to the dirt collection chamber sidewall 56 b. Referring to FIG.40, this embodiment is similar to the embodiment of FIG. 39, but isconfigured so that air will circulate in the opposite direction. In bothembodiments, the dirt slot partially overlaps the air inlet.

Referring to FIG. 41, in this embodiment the dirt slot 44 d is locatedin a third quadrant of the cyclone chamber, where the angle 60 d isgreater than 180 degrees. As illustrated, the angle 60 d is about 130degrees. In this embodiment the dirt slot 44 d covers an angle 58 d ofabout 80 degrees.

Referring to FIG. 42, in this embodiment the dirt slot 44 e is about 125degrees downstream from the air inlet 42 e (i.e. the angle 60 e is about125 degrees), and sweeps an angle 58 e of about 70 degrees. In thisembodiment the upstream end of the dirt slot 44 e is located at theintersection of the cyclone chamber sidewall 41 e and the dirtcollection chamber sidewall 56 e.

Referring to FIG. 43, in this embodiment the dirt slot 44 f overliessubstantially all of the air inlet 42 f and the angle 60 f (measured inthe direction of air flow) is about 325 degrees (i.e. the dirt slot 44 fis located about 45 degrees upstream from the air outlet 42 f). In thisconfiguration, the downstream end of the dirt slot 44 f is located atthe intersection between the cyclone chamber sidewall 41 f and the dirtcollection chamber sidewall 56 f.

The dirt collection chamber 11 may be of any suitable configuration.Referring to FIG. 21, in the illustrated example, the dirt collectionchamber 11 includes a first end wall 61, a second end wall 62 and thesidewall 56 extending therebetween.

To help facilitate emptying the dirt collection chamber 11, at least oneof or both of the end walls 61, 62 may be openable. Similarly, one orboth of the cyclone chamber end walls 39 and 40 may be openable to allowa user to empty debris from the cyclone chamber. Referring to FIGS. 21and 24, in the illustrated example, the upper dirt chamber end wall 61is integral with the upper cyclone end wall 39 and the lower dirtcollection chamber end wall 62 is integral with, and openable with, thelower cyclone chamber end wall 40 and both form part of the openablebottom door 63. The door 63 is moveable between a closed position (FIG.21) and an open position (FIG. 24). When the door 63 is open, both thecyclone chamber 10 and the dirt collection chamber can be emptiedconcurrently. Alternatively, the end walls of the dirt collectionchamber 11 and the cyclone chamber 10 need not be integral with eachother, and the dirt collection chamber 11 may be openable independentlyof the cyclone chamber 10.

Cyclone with Curved or Angled Surfaces

The following is a description of a cyclone construction that may beused by itself in any surface cleaning apparatus or in any combinationor sub-combination with any other feature or features disclosed herein.

Referring to FIG. 21, in the illustrated embodiment, the upper end wall39 closes the upper end of the sidewall 41. In the illustrated example,the intersection or juncture 64 between the end wall 39 and the sidewall 41 is a relatively sharp corner that does not include any type ofangled or radiused surface. In contrast, the lower end wall 40preferably meets the lower end of the cyclone sidewall 41 at a juncture65 that may comprise an angled or a curved juncture surface 66 (see alsoFIG. 22). The radius 67 of the curved surface 66 may be selected basedon the radius of the air inlet 42 (e.g. half of the diameter 48), andoptionally may be the selected so that the juncture surface 66 has thesame radius as the air inlet 42.

Optionally, the curved juncture surface 66 can be formed as a portion ofthe sidewall 41 or as a portion of the end wall 40. In the illustratedembodiment, the curved juncture surface 66 is provided as part of aninsert member 68 (FIG. 24) that is provided on the bottom end wall 40and extends upward into the interior of the cyclone chamber 10.

Alternately, or in addition, the juncture between the vortex finder 49and the end wall 40 may also be provided with an angled or curvedsurface. In the illustrated embodiment, the juncture 70 between the endwall 40 and the vortex finder 49 may also include a curved surface 72.The curved surface 72 can be sized to have a radius 71 that is the sameas the radius 67 of the juncture 66 between the end wall 40 and thesidewall 41. Providing curved surfaces 66, 72 at one or both of thejunctures 65, 70 may help reduce backpressure and may help improvecyclone efficiency. In the illustrated embodiment, the radii 65 and 70are equal to the radius of the air inlet 42. Alternatively, the radii 65and 70 may be different.

In the illustrated example, member 68 provides the juncture surface 72.Optionally, the curved juncture surfaces within the cyclone chamber 10(e.g., member 68) may be removable from the cyclone chamber 10 when thecyclone chamber is opened. In the illustrated embodiment, the member 68is provided on the movable door 63, and is removed from the cyclonechamber 10 when the door 63 is opened. The vortex finder 49 and screen50 are also mounted to the door 63 and are removed from the cyclonechamber 10 when the door opens. Removing some of all of the curvedjuncture surfaces 66, 72 from the cyclone chamber 10 when the door 63 isopened for emptying may help ensure dirt and debris can fall out of thecyclone chamber without settling on or otherwise becoming hung-up on thejuncture surfaces 66, 72. Alternatively, the juncture surfaces may beformed as part of the sidewall 41, or otherwise fixed within the cyclonechamber 10 such that the juncture surfaces are not removable from thecyclone chamber 10 and do not move with the door 63. A further advantageis that member 68 may abut the inner surface of the sidewall of thecyclone chamber and the lower edge of the sidewall may engage a gasketor other sealing member provided in a recess on the door 63. Such aconstruction provides an enhanced seal when a curved openable door isprovided.

Optionally, the juncture surfaces 66 and 72 may be positioned such thatthey abut each other to form a generally continuous curved or angledsurface (or a combination of a curved surface and an angled or inclinedsurface). If the radii of curvature of the surfaces 66 and 72 are equal,the surfaces 66 and 72 may co-operate to form a surface with a generallyconsistent curvature (e.g., a half toroid shape) that may approximatethe shape and curvature of the air inlet 42. Matching the curvature ofthe juncture surfaces 66 and 72 to the curvature to the air inlet 42 mayhelp improve cyclone performance. Alternatively, the curvature of thejunctures 66 and 72 need not match the curvature of the air inlet 42.

Alternatively, the juncture surfaces 66 and 72 may be radially spacedapart from each other such that they do not connect directly to eachother. In such embodiments, a transition or bridge region may be definedbetween the juncture surfaces 66, 72. Referring to FIG. 24, in theillustrated embodiment the juncture surfaces 66 and 72 are radiallyseparated from each other by a bridge surface 73 that has radial width74 (FIG. 21). The width 74 may be any suitable width, including, forexample, between and 3% and about 15% or more of the diameter 48 of theair inlet 42. Optionally, the width 74 may be greater than 0.5%, such asbetween about 0.5-12%, 3%-12%, 3%-7% and 3%-5% of the diameter 48. Inthis configuration, the juncture surfaces 66 and 72 are separate fromeach other, and from bridge surface 73.

Optionally, in addition to (or as an alternative to) the member 68 onthe bottom wall 40, an additional insert member may be provided withinthe cyclone chamber 10, and may be located toward the upper end wall 39.In the illustrated embodiment, an upper insert member 76 is provided atthe upper end of the cyclone chamber 10. The insert member 76 includes adownwardly extending central wall or projection member 77 that extendsinto the interior of the cyclone chamber 10 and may optionally engagethe distal end 78 of the screen 50 (FIG. 21). Together, the vortexfinder 49, screen 50 and projection member 77 may form a generallycontinuous internal column member that extends between the first andsecond end walls 39 and 40 of the cyclone chamber. Providing theprojection member 77 may help direct air flow within the cyclonechamber, and may help support and/or stabilize the distal end 78 of thescreen 50.

Optionally, the juncture 79 between the end wall 39 and the projectionmember 77 may include a curved juncture surface 80 (see FIGS. 21 and22). The surface 80 is curved and defines a radius 81. The radius 81 maybe any suitable radius, and in the illustrated embodiment is the same asradii 66 and 72. Providing curved surfaces 80 at the junctures betweenthe end wall 39 and the projection member 77, may help reducebackpressure and may help improve cyclone efficiency. Optionally, insome embodiments the juncture 64 may also include an angled or curvedsurface.

In the illustrated embodiment, the bottom of the air inlet 42 isgenerally aligned with the surface of the member 68, such that the airinlet 42 is positioned at the bottom of the cyclone chamber 10.

The radial distance 81 (FIG. 21) between the cyclone chamber sidewall 41and the surface 54 of the vortex finder 49, which form an upstandingwall portion of the member 68, may be any suitable distance. Preferably,the distance 81 is greater than the air inlet width 48 such that thevortex finder 49 is radially offset from the edge of the air inlet 42 byan offset distance 82. The offset distance 82 may be any suitabledistance, and may, for example, be between about 0% and about 100% ormore of the air inlet width 48, between about 2% and about 25% of thewidth 48, between about 5% and about 15% of the width 48 and may beabout 10% of the width 48. Altering the distance 81 may affect theefficiency and performance of the cyclone.

In the illustrated embodiment, the air inlet 42 is positioned at thejuncture 65 between the sidewall 41 and the end wall 40 and ispositioned such that the air inlet 42 is adjacent the sidewall 41 (i.e.,there is no radial gap between the outer edge of the air inlet 42 andthe sidewall 41). Alternatively, the air inlet 42 may be spaced radiallyinwardly from the sidewall 41 such that a gap is provided between theedge of the air inlet 42 and the sidewall 41.

It will be appreciated that if the air outlet is provided in wall 39,then insert member 76 may be configured as vortex finder 49 and vortexfinder 49 may be configures as insert member 76.

In the embodiment FIG. 25, the juncture 1065 between the sidewall 1041and the bottom wall 1040 is not rounded, but instead includes an angledsurface 1066. The angle of the surface 1066 is selected so that thejuncture surface 1066 is generally tangential to the air inlet 1042. Inthe illustrated example, the surface 1066 extends generally continuouslyfrom the sidewall 1041 to the bridge surface 1073. In this example thejuncture surface 1072 is rounded, as described in detail above.

The air inlet and the vortex finder are preferably sized such that thetop (upper inward extent) of the air inlet is below the innermost end ofthe vortex finder. For example, in the illustrated embodiment, thebottom of the air inlet 1042 is adjacent the bottom wall 1040 and thetop of the air inlet 1042 is spaced apart from the bottom wall by aheight 1094, which in the illustrated configuration is equal to thediameter 1048. The vortex finder 1049 also extends away from the bottomwall 1040 and has a height 1096 measured in the axial direction. In thisembodiment, the height 1096 is greater than the height 1095 and theupper end of the vortex finder 1049 is offset above the top of the airinlet 1042 by a distance 1097. The distance 1097 can be any suitabledistance, and may be, for example, between 0% and about 25% or more ofthe air inlet diameter 1048 (e.g., between about 0.05-1 inches,preferably between about 0.1-0.5 inches and more preferably about 0.25inches). Alternatively, the top of the air inlet 1042 can be flush with,or extend above the top of the vortex finder 1049.

Referring to FIGS. 26-37, additional embodiments of a cyclone binassembly are illustrated. Each embodiment is generally similar tocyclone bin assembly 9, and analogous features are identified using likereference numerals indexed by a given amount (2000, 3000, 4000, etc.).Features of any one embodiment of the cyclone bin assembly may becombined in combination or sub-combination with any compatible featuresfrom any of the other embodiments of the cyclone bin assembly.

Referring to FIG. 26, in this embodiment the juncture surface 2066 iskinked as opposed to being a generally flat surface as shown in FIG. 25.In this embodiment, the juncture surface 2066 is not tangential to thesidewall of the air inlet 2042. In this illustrated example, thejuncture surface 2072 is curved with a radius that generally matches thecurvature of the air inlet 2042 and the bridge surface 2073 extendsbetween surfaces 2072 and 2066 and has a width 2074. In this embodiment,the screen 2050 is generally cylindrical and has a constant width alongits entire height.

Referring to FIG. 27, in this embodiment, the juncture 3065 between thesidewall 3041 and the bottom wall 3040 forms a sharp corner and is notangled or radiused and the juncture 3070 between the bottom wall 3040and the vortex finder 3049 is also formed as a sharp corner. While thelower junctures are both formed as sharp corners, the juncture surface3080 extending between the upper wall 3039 and the insert 3076 remains acurved surface with radius 3081. In this configuration, the air inlet3042 is positioned in juncture 3065 and is tangential to both thecyclone chamber sidewalls 3041 and the bottom wall 3040. Further, abridge surface is provided.

Referring to FIG. 28, in this embodiment, juncture surfaces 4066 and4072 are both curved surfaces but radiuses 4067 and 4071 are different.In the illustrated example, radius 4067 is smaller than the curvature ofthe air inlet 4042 such that the surface 4066 is not aligned with theside of the air inlet 4042. Optionally, the radius 4071 can be selectedto match the curvature of the air inlet 4042.

Referring to FIG. 29, in this embodiment, the member 5068 is configuredsuch that the radial distance 5081 between the cyclone chamber sidewall5041 and the vortex finder 5049 is the same as the diameter 5048 of theair inlet 5042. In this configuration, there is no gap between a radialdistance in equal to the diameter of the air inlet 5042 and the vortexfinder 5049. In the example illustrated, juncture surfaces 5066 and 5072are both curved surfaces and are configured so that the radiuses 5067and 5071 are the same and are selected to match the curvature of the airinlet 5042. In this configuration, substantially all of the lower halfof the air inlet 5042 is aligned with the juncture surfaces 5066 and5072. In this embodiment, the juncture surface 5080 is also curved. Whenconfigured in this matter, juncture surfaces 5066 and 5072 meet so as toform one generally continuous curve surface that extends from thecyclone chamber sidewall 5041 to vortex finder 5049.

Referring to FIG. 30, in this embodiment, juncture surface 6066 iscurved with a curvature that is selected to match the shape of air inlet6042 whereas juncture 6070 is formed as a sharp corner.

Referring to FIG. 31, in this embodiment, the cyclone chamber 7010 andmember 7068 are configured such that the radial distance 7081 betweenthe cyclone chamber sidewall 7041 and the vortex finder 7049 issubstantially larger than the diameter 7048 of the air inlet 7042. Inthis configuration, the width 7074 of the bridge surface 7073 isrelatively large and in the example illustrated, is greater than theradial width 7098 of juncture surface 7066. In this example, bothjuncture surfaces 7066 and 7072 are both curved surfaces and areconfigured such that their curvature generally matches the shape of airinlet 7042.

Referring to FIG. 32, in this embodiment, member 8068 is configured sothat the juncture 8065 has an angled or inclined juncture surface 8066and the juncture 8070 is formed as a sharp corner. Illustrated as acurved, juncture surface 8080 can optionally be configured as a sharpcorner or as an inclined or angled surface.

Referring to FIG. 33, in this embodiment member 9068 is configured sothat the juncture between 9070, between bottom wall 9040 and vortexfinder 9049 is configured as a sharp corner and juncture 9065 betweenthe bottom wall 9040 and the cyclone chamber sidewall 9041 includes acurved juncture surface 9066. The curvature of juncture surface 9066 isselected to generally match the curvature of air inlet 9042. In thisconfiguration, the air inlet 9042 is provided at a different locationwithin the cyclone chamber 9010, but is still positioned generallytangential relative to cyclone chamber sidewall 9041. Changing theposition of the air inlet 9042 may affect the air flow within thecyclone chamber and, in the example illustrated, may result in aircirculating within the cyclone chamber 9010 in the direction that isgenerally opposite to the direction of air circulation in the cyclonechambers of the previous embodiments. Also, in this configuration, theair inlet 9042 is located adjacent and generally below the dirt outletslot 9044.

Referring to FIG. 34, in this embodiment, member 10068 is configured sothat outer juncture 10065 (between cyclone chamber sidewall 10041 andbottom wall 10040) is configured as a generally sharp corner and innerjuncture 10070 is configured as a curved surface. In this embodiment,the air inlet 10042 is generally rectangular (as opposed to beinggenerally circular as in the previous embodiments) and has an air inletheight 10096. In the cited example, the air inlet height 10096 is stillless than the height of the vortex finder 10049 thereby providing a gapof height 10097 between the top of the air inlet 10042 and top of thevortex finder 10049. In this embodiment, the sharp corner configure ofjuncture 10065 generally matches the shape of the lower portion of theair inlet 10042 and the air inlet is generally tangential to the cyclonechamber sidewall 10041.

Referring to FIG. 35, in this embodiment the air inlet 11042 is apartially rectangular partially curved configuration. In the illustratedexample, the lower portion of the air inlet 11042 located towards theinner section of the cyclone chamber sidewall 11041, and the lower wall11040 is curved, and the surface 11072 at juncture 11070, is a curvedsurface that is configured to generally match the shape of the air inlet11042. The juncture 11065 between the lower end wall 11040 and thevortex finder 11049 is configured as a sharp corner. Also in thisexample, the air inlet 11042 is positioned toward the center of thecyclone bin of the assembly 11009 and is adjacent to a portion of thecyclone chamber sidewall 11041 that separates the cyclone chamber 11010from the dirt collection chamber 11011.

Referring to FIG. 36, this embodiment is generally similar to theembodiment of FIG. 35 but the air inlet 12042 is of a differentconfiguration than air inlet 11042. In this example, the lower portionof the air inlet 12042 is curved and the juncture 12070 is also curvedso that the juncture surface 12072 generally matches the shape of theair inlet 12042. The juncture 12065 between the bottom wall 12040 andthe vortex finder 12049 is configured as a generally sharp corner.

Referring to FIG. 37, in this embodiment, member 13068 is configured sothat the bottom wall 13040 of the cyclone chamber 13010 is spaced belowthe bottom of the air inlet 13042. In the illustrated example, thebottom wall 13040 is offset below the bottom of the air inlet 13042 bydistance 13099. The distance 13099 may be any suitable distance, and maybe between about 0% and about 50% of the diameter 13048 of the air inlet13042. In this example, junctures 13065 and 13070 are both curved butbecause of the vertical offset 13099, portions of the juncture 13070 arespaced apart from the edges of the air inlet 13042.

As exemplified in the forgoing, the juncture of the sidewall and the endwall at the cyclone air inlet end is preferably configured to permit airexiting the air inlet to transition smoothly (e.g., without forming eddycurrents or other turbulence) as the air enters the cyclone chamber.Accordingly, the juncture of the side and end walls is preferablyconfigured to match the shape of the cyclone air inlet and the cycloneair inlet is preferably positioned adjacent the juncture. However, asexemplified, the juncture may be angled so as to approximate thecurvature of the air inlet. Alternately, if the air inlet is notcircular, the juncture may be shaped similarly to the portion of the airinlet that abuts the juncture or may approximate the shape. As alsoexemplified, the air inlet may be spaced from the juncture of the sideand end walls (e.g., above and/or inwardly therefrom) but may abut thesidewall and/or end wall inwards of the juncture.

Alternately or in addition, the juncture of the sidewall of a vortexfinder (or insert) and an end wall may be shaped to match the shaped ofthe juncture of the sidewall and the end wall at the air inlet or may beangled or curved so as to reduce eddy currents or turbulence.

Alternately, or in addition, distance between the sidewall and thevortex finder and/or the innermost end of the vortex finder and the endwall may be greater than the diameter of the air inlet.

It will be appreciated that, in a preferred embodiment, each of thesefeatures is used. However, the use of any of the features maybeneficially reduce eddy currents or other turbulence in the cyclonechamber and thereby reduce back pressure through the cyclone chamber. Areduction in the back pressure through the cyclone chamber mill permitthe velocity of air flow at the dirty air inlet to be increased, allother factors remaining the same, and thereby increase the cleaningefficiency of a vacuum cleaner.

Barrier Wall

The following is a description of a barrier wall that may be used byitself in any surface cleaning apparatus or in any combination orsub-combination with any other feature or features disclosed herein.

Referring to FIGS. 44-54, schematic representations of alternateembodiments of a cyclone chamber and dirt collection chamber are shown.These schematic representations are generally similar to the cyclonechamber 10 and dirt collection chamber 11, and analogous features areidentified using like reference characters with a unique suffix.

Referring to FIG. 44, a cyclone chamber 10 g is illustrated incombination with a dirt collection chamber 11 g. The cyclone chamber 10g includes an air inlet 42 a, air outlet (not shown), sidewall 41 a anda dirt outlet 44. For ease of description the upper walls of the cyclonechamber 10 g and dirt collection chamber 11 g have been removed, but itis understood that the upper ends of the dirt collection chamber 11 gand cyclone chamber 10 g can be covered with any suitable upper wall orlid. The air inlet 42 a is provided toward the bottom end of the cyclonechamber 10 g and the dirt outlet 44 g is provided toward the top of thecyclone chamber 10 g. Alternatively, the positions of the air inlet 42 gand dirt outlet 44 g may be reversed.

In the illustrated embodiment, a deflector or barrier wall 83 g ispositioned in the dirt collection chamber 11 g generally opposite thedirt outlet 44 g. In this position, dirty air exiting the cyclonechamber 10 g may tend to contact the barrier wall 83 g, which may helpdis-entrain dirt and debris from the air flow. The barrier wall 83 g mayalso guide or direct dirt particles in a desired direction within thedirt collection chamber 11 g. Alternatively, instead of being positionedwithin the dirt collection chamber 11 g, the barrier wall 83 g may beprovided in any other air passage or conduit that is in air flowcommunication between the dirt outlet 44 g and the dirt collectionchamber 11 g (for example if the dirt outlet 44 g is not in directcommunication with the dirt collection chamber 11 g).

The barrier wall 83 g has a first or inner face 84 g that faces and isspaced from the dirt outlet 44 g and an opposed outer face 85 g that isspaced from and faces the sidewall 56 g of the dirt collection chamber11 g. The barrier wall 83 g also defines an upstream end 86 g and adownstream end 87 g relative to the direction of air circulation withinthe cyclone chamber 10 g. Barrier wall may be fixed in position by anymeans. For example, it may be affixed to the cyclone chamber sidewall,the end wall or a sidewall of the exterior dirt collection chamber. Inthe illustrated embodiment the barrier wall 83 g extends from thecyclone chamber sidewall 41 g, and the upstream end 86 g of the barrierwall 83 g is connected to the cyclone chamber sidewall 41 g at alocation upstream from the upstream end of the slot 44 g, and is sealedagainst the sidewall 41 g. The downstream end 87 g of the barrier wall83 g is spaced apart from the cyclone chamber sidewall 41 g.Alternatively, the upstream end 86 g of the barrier wall 83 g may bespaced apart from the cyclone chamber sidewall 41 g. If the barrier wallis connected to or extends from the sidewall of the cyclone chamber,then the position from which the barrier wall extends is preferably upto 1 inch and more preferably 0.125 to 0.5 inches upstream from theupstream side of the dirt outlet.

The barrier wall 83 g is radially spaced apart from the dirt outlet 44 gand the cyclone chamber sidewall by a distance 88 g. In the illustratedembodiment the distance 88 g is generally constant and the distancebetween the upstream end of the dirt slot and the barrier wall 83 g isthe same as the distance between the downstream end of the dirt slot andthe barrier wall 83 g (i.e. most of the barrier wall 83 g is generallyconcentric with or parallel to the cyclone chamber sidewall 41 a). Thedistance 88 g may be selected to be any suitable distance, andpreferably is large enough to allow debris to pass between the barrierwall 83 g and the sidewall 41 g. For example, the distance 88 g may beselected to be up to 1.5 inches or more, and may be configured to beless than 1 inch (e.g., 0.5-0.075 inches) and may be between about 0.125and 0.5 inches. If the surface cleaning apparatus is to be used toclean, e.g., dry wall dust, then the spacing may be between 0.075-0.2inches. In configurations in which one end of the barrier wall 83 flaresaway from the cyclone chamber sidewall 41 downstream from the dirtoutlet (as explained herein), the distance between the flared portion ofthe barrier wall and the cyclone chamber sidewall 41 may exceed theranges given above. For example, the distance between the cyclonechamber sidewall and the barrier wall at the downstream end of the dirtoutlet may be between 10-50% further from the cyclone chamber sidewallthan the distance between the cyclone chamber sidewall and the barrierwall at the upstream end of the dirt outlet and is preferably about10-20% further.

In the illustrated embodiment, the barrier wall 83 g is slightly widerin the axial direction than the dirt outlet slot 44 g, so that thebarrier wall 83 g covers or overlaps the full width of the dirt slot 44g (e.g., it has a similar angular extent). Alternatively, the barrierwall 83 g may have a width that is equal to or less than the width ofthe dirt slot 44 g.

The height of the barrier wall may be from 35-150% the height of thedirt outlet. For example, in the illustrated embodiment, the barrierwall 83 g extends substantially the entire height of the cyclone chamber10 g in the axial direction, and the height of the barrier wall 83 g isgreater than the height 57 g of the dirt slot 44 g. In this embodimentthe barrier wall 83 g has a constant height along its width, butalternatively the height of the barrier wall 83 g may vary along itswidth (e.g. the upstream end of the wall may be taller than thedownstream end, or vice versa).

Referring to FIG. 45, in another embodiment, the barrier wall 83 h doesnot extend the full height of the cyclone chamber 10 h, and the upperend of the barrier wall 83 h is axially offset below the upper end ofthe cyclone chamber sidewall 41 h. In this configuration, the barrierwall 83 h does not cover the full axial height of the dirt outlet 44 h,but does extend to cover the full width of the dirt outlet 44 h.

Also in this embodiment, the barrier wall 83 h is not parallel to orconcentric to the sidewall 41 h. In this configuration, the distance 88h between the upstream end of the slot 44 h and the barrier wall 83 h isless than the distance 88 h between the downstream end of the slot 44 hand the barrier wall 83 h. Further, the barrier wall 83 h continues todiverge from the sidewall 41 h so that the distance 88 between thebarrier wall 83 h and the sidewall 41 at a location downstream from theslot 44 h is greater than the distance 88 g at the downstream end of theslot 44 h.

Referring to FIG. 46, in another embodiment a barrier wall 83 i flaresmore substantially away from the outer surface of the cyclone chambersidewall 41 i so that the distance 88 i at the downstream end of thedirt slot 44 i is much greater than the distance 88 i at the upstreamend of the slot 44 i.

Referring to FIG. 47, in another embodiment a barrier wall 83 j has awidth that is less than the width of the dirt slot 44 j. In thisconfiguration, the barrier wall 83 j covers the upstream end of the slot44 j and a portion of its width, but the downstream end 87 j of thebarrier wall 83 j does not reach or cover the downstream end of the slot44 j.

Referring to FIG. 48, in another embodiment a barrier wall 83 k extendsthe full width and full height of the dirt slot 44 k, but is configuredsuch that the upstream end 86 k of the barrier wall 84 k is spaced apartfrom the sidewall 41 k to provide a passage 89 k between the wall 83 kand the sidewall 41 k. In this configuration the barrier wall 83 k isnot supported by the sidewall 41 k and instead may extend upward fromthe bottom wall of the dirt collection chamber 11 g. Alternatively, orin addition, one or more optional support ribs 90 k (illustrated asoptional using dashed lines) may extend between the dirt collectionchamber sidewall 56 k (and/or from sidewall 41 k) and the barrier wall83 k to help provide support.

Alternatively, instead of extending upwardly from the bottom wall of thedirt collection chamber, the barrier wall may depend downwardly from theupper wall of the dirt collection chamber. Referring to FIG. 49, inanother embodiment a barrier wall 83L extends downwardly from the upperwall of the dirt collection chamber 11L and is sized to cover dirt slot44L. Optionally, referring to FIG. 50, a barrier wall 83 m that dependsfrom the upper wall of the dirt collection chamber 11 m can beconfigured to have a height that is less than the height of the cyclonechamber 10 m, and optionally less than the height 57 m of the slot 44 m.

Optionally, some or all of the barrier wall may be integral with otherportions of the cyclone chamber or dirt collection chamber. Referring toFIG. 51, in another embodiment a barrier wall 83 n is integral with thedirt collection chamber sidewall 56 n or optionally a passage extendingto a dirt collection chamber. In this embodiment, the inner surface 84 nof the barrier wall 83 n faces the cyclone chamber sidewall 41 n and theouter surface 85 n may be part of the exterior surface of the cyclonechamber assembly (or optionally surrounded by another housing, etc.). Ifthe barrier wall is integral with other portions of the cyclone chamberor the dirt collection chamber or a passage thereto, it preferablyextends from a position somewhat upstream from the upstream end of thedirt outlet.

Referring to FIG. 52, in another embodiment the barrier wall 88 o has avariable height, and in the configuration illustrated, increases inheight from the upstream end 86 o toward the downstream end 87 o. In theillustrated configuration, the upstream end 86 o of the barrier wall 83o does not cover the full height 57 o of the slot 44 o, whereas thedownstream end 87 o covers more of the full height of the slot 44 o.FIG. 53 is a section view showing the elevation of the barrier wall 83 orelative to cyclone chamber 10 o and slot 44 o. FIG. 54 is an alternateembodiment in which the barrier wall 83 p varies in height in theopposite direction (the upstream end 86 p is shorted than the downstreamend 87 p).

Dirt Slot of Varying Heights

Referring to FIGS. 55-57, schematic representations of alternateembodiments of a cyclone chamber 10 are shown. The schematic embodimentsare generally similar to the cyclone chamber 10, and analogous featuresare identified using like reference numerals with a unique suffix.

Referring to FIG. 55, the cyclone chamber 10 q includes a dirt slot 44 qthat varies in height 57 q along its width. In this embodiment, theheight 57 q at the upstream end of the slot 44 q is less than the height57 q at the downstream end of the slot 44. Also, in this embodiment theintersection of the upstream edge 91 q and the bottom edge 92 q isrounded, as is the intersection between the downstream edge 93 q and thebottom edge 92 q. Alternatively, only one of these intersections may berounded.

Referring to FIG. 56, in another embodiment the slot 44 r is configuredso that there are sharp corners between edges 91 r and 93 r and bottomedge 92 r, and that the upstream end of the slot 44 r is taller than thedownstream end.

The slot 44 r (and any other dirt outlet slot) can be configured so thatthe height at the shortest portion of the slot is between about 35% toabout 100% (i.e. no change) of the height at the tallest portion of theslot.

The features of the dirt slot illustrated in the above embodiments maybe used by itself or in any combination or sub-combination with anyother feature or features disclosed herein.

Pre-Motor Filter Housing Construction

The following is a description of a pre-motor filter housing that may beused by itself in any surface cleaning apparatus or in any combinationor sub-combination with any other feature or features disclosed herein.

Referring to FIG. 57, a schematic representation of a surface cleaningunit 4 is shown. In the illustrated example, two pre-motor filters 32and 33 are positioned within the pre-motor filter chamber 31, although adiffering number may be used. The pre-motor filter chamber 31 is definedby a housing that comprises an upper end wall 110 that may optionallyinclude the downstream end of the vortex finder, a sidewall 111 and alower end wall 112 that may optionally include the upstream end of thesuction motor inlet.

The open headspace or header between the bottom of the cyclone binassembly and the upper side 123 of the filter 32 defines an upstream airplenum 124. Providing the upstream plenum 124 allows air to flow acrossthe upper side 123 of the filter 32. The open headspace or headerdownstream of the filters 32, 33, between the downstream side 125 offilter 33, provides a downstream air plenum. Providing a downstreamplenum 126 allows air exiting the filters 32, 33 to flow inwardly andtoward the suction motor inlet. In use, air exiting the cyclone chamber10, via the air outlet 43, flows into upstream plenum 124, throughfilters 32, 33, into downstream plenum 126 and into the air inletportion 113 of the suction motor 8.

As exemplified in FIG. 17, the outer sidewall of the motor housing 12may surround some or all of the pre-motor filter chamber 31. Further,most or all of the upper end wall 110 may be provided by the lowersurface of the cyclone bin assembly 9, including portions of the cyclonechamber end wall 40 and the dirt collection chamber end wall 62. In thisconfiguration, when the cyclone bin assembly 9 is removed, most of theupper end wall 110 is also removed, which may “open” the pre-motorfilter chamber 31 and allow a user to access the filters 32, 33.Similarly, most of the lower end wall 112 is provided by the suctionmotor inlet sidewall 114.

Optionally, the pre-motor filter housing has an upstream and/or adownstream header that is configured to reduce turbulence. Accordingly,some or all of the intersections between, the walls 110 and 111, thewalls 111 and 112, and the wall 112 and the suction motor inlet mayinclude angled or curved surfaces, which may be shaped in a similarmanner to the configuration of the junctures of the cyclone chamber 10discussed previously. Providing curved or smoother junctures within thepre-motor filter housing 31 may help reduce backpressure caused by thepre-motor filter chamber. This may help improve the efficiency of thesurface cleaning apparatus 1 by increase the velocity of the air flow atthe dirty air inlet, all other factors remaining the same. Improving theefficiency may allow the surface cleaning apparatus to provide improvedsuction capabilities, and/or may allow the surface cleaning apparatus tomaintain its existing suction capabilities while requiring a smaller,less powerful motor 8.

In the illustrated embodiment, the juncture 115 between the sidewall 111and the upper wall 110 includes a curved juncture surface 116. Thecurvature of the surface 116 can be selected to help improve air flowinto the upstream plenum 124. Optionally, the juncture surface 116 canremain with the pre-motor filter chamber 31 when the cyclone binassembly 9 is removed, or alternatively the juncture surface 116 may bepart of the cyclone bin assembly 9 and may be removable from thepre-motor filter chamber 31.

The juncture 117 between the sidewall 111 and the wall 112 forming partof the suction motor inlet 113 also includes a curved juncture surface118. The curvature of surface 118 may be the same as, or different thanthe curvature of surface 116. Optionally, the juncture between the wall112 and the inlet sidewall 114 of the suction motor inlet may also becurved or angled. In the illustrated embodiment, the juncture 119between walls 112 and 114 includes a curved surface 120, which may helpimprove air flow into the suction motor 8. Alternatively, instead ofbeing curved, junctures surfaces 116, 118 and 120, as well as thejuncture of the vortex finder and wall 110, may be generally planarangled or inclined surfaces. The curvature of surfaces 116, 118 and 120may be any of suitable magnitude that helps improve air flow efficiencythrough the pre-motor filter chamber 31 and suction motor air inlet 113.

A generally flat bridging surface 121 forms part of wall 112 and extendsbetween juncture surfaces 118 and 120 and has a length 122. Together,the juncture surfaces 118 and 120 and surfaces 121 and 114 mayco-operate to form a generally flared or trumpet-like motor inlet 113.As illustrated, the vortex finder may also be flared or trumpet-shaped.

Referring to FIG. 58, another embodiment of a surface cleaning unit14004 is shown. Surface cleaning 14004 is generally similar to surfacecleaning unit 4, and analogous features are identified using likereference characters indexed by 14000.

In the illustrated embodiment, the surface cleaning unit 14004 includesa cyclone bin assembly 14009 that is positioned below the suction motor14008 and suction motor housing 14012. The pre motored filter chamber14031, containing filter 14032 and 14033, is located between cyclone binassembly 14009 and the suction motor 14008 and the illustratedconfiguration is positioned above cyclone bin assembly 14009.

In this embodiment, air enters the cyclone chamber 14010 via air inlet14042 and exits via air outlet 14043. Air then flows into the upstreamheader or plenum 14125 before contacting the upstream face 14123 offilter 14032 and flowing through the filters 14032 and 14033 into thedownstream headspace or plenum 14126. From the downstream plenum 14126,air is guided by walls 14112, 14114, to the air inlet of the suctionmotor 14008. Like the previous embodiment, juncture 14115 between theend wall 14110 and the side wall 14111 includes a curved or a radiusedsurface 14116 to help improve air flow. Similarly junctures 14117 and14119 provided in the downstream plenum 14126 include curved or radiussurface 14118 and 14120, respect to the leak. A flat bridging surface14121 connects curved surfaces 14118 and 14120 and helps provide theflared or trumpet like inlet for the suction motor 14008.

Referring to FIG. 59, the embodiment of FIG. 58 is shown having curvedjuncture surfaces 14118 and 14120 that have a larger radius or degree ofcurvature than those shown in FIG. 58. A bridge surface 14121 is stillprovided between surfaces 14120 and 14118 but its length 14122 in theembodiment of FIG. 59 is substantially less than its length in theprevious embodiment. The curvature of juncture surface 14116 remainsunchanged from the embodiment of FIG. 58. Providing a higher degree orcurvature and/or larger curved juncture surfaces 14118, 14120 may helpimprove air flow from the downstream plenum 14126 to the suction motor14008.

Referring to FIG. 60 another embodiment of the surface cleaning unit15004 is shown. Surface cleaning unit 15004 is generally similar tosurface cleaning unit 4 and analogous features are identified using likereferencing characters indexed by 15000. In the illustrated embodimentthe cyclone bin assembly 15009 is positioned above the suction motor15008 and surrounding housing 15012, and the pre-motor chamber 15031 isdefined there between.

In the illustrated embodiment air enters cyclone chamber 15010 via inlet15042 and exists via air outlet 15043. In this configuration air outlet15043 is not directly connected to upstream plenum 15124 and instead isconnected via an external air flow conduit 15127 which is providedoutside cyclone chamber 15010 and provides air flow communicationbetween air outlet 15043 and plenum 15124.

As in the previous embodiment, air exiting the cyclone chamber 15010goes into upstream plenum 15124, through filters 15032, 15033 and intodownstream plenum 15126. In this embodiment, the juncture 15115 betweenupper wall 15110 and side wall 15111 is not curved, and instead and isformed as a sharp corner. Juncture 15117 and 15119 provided downstreamof the filters 15032, 15033 are curved in this embodiment and includecurved juncture services 15118 and 15120 respectively.

Suction Motor Air Inlet

The following is a description of a suction motor air inlet that may beused by itself in any surface cleaning apparatus or in any combinationor sub-combination with any other feature or features disclosed herein.

Referring to FIG. 61, the suction motor housing 12 is shown separatedfrom the upper portion 2, and with the cyclone bin assembly 9, filters32, 32 and door 13 removed. In this embodiment, the suction motorhousing 12 includes the sidewall 111 and the bottom wall 112 that boundpart of the pre-motor filter chamber 31. The bottom wall 112 includes aplurality of optional supporting ribs 130 that project upwards from thewall 112 into the chamber 31. The ribs 130 are configured to contact thedownstream side 125 of the filters (in this example felt filter 33) inthe chamber 31 and to hold it above the wall 112, thereby help tomaintaining the downstream plenum 126 (FIG. 57). The ribs 130 are spacedapart from each other to allow air to flow between them, within theplenum 126, and toward the suction motor air inlet 113.

Optionally, some or all of the support ribs in the pre-motor filterchamber 31 may be configured to help guide or direct the air flowingthrough the downstream plenum 126. For example, some of the ribs may beconfigured to help induce rotation of the air within the plenum 126,before it flows into the suction motor 8. Preferably, this pre-rotationof the air flow can be selected so that the air is rotated in thedirection of revolution of the fan of the suction motor 8. Pre-rotatingthe air in this manner may help improve the efficiency of the surfacecleaning unit 4. The ribs may be configured in any suitable manner tohelp impart rotation to the air flow.

In the illustrated embodiment, the plurality of ribs 130 includes aplurality of curved ribs 131 that are provide around the suction motorair inlet 113. The ribs 131 are curved to impart rotation of the airflow in the direction indicated by arrow 132, which preferably is thesame direction as the direction of revolution of the suction motor 8.

The ribs 130 define a rib height 133. If the lower wall 112 of thepre-motor filter is flat, the height 133 of each rib 130, 131 may remainconstant along its entire with. Alternatively, if the lower wall 112varies in height (e.g., the extend inwardly along a portion of atrumpet-shaped suction motor inlet), the ribs 130, 131 may also vary inheight. Preferably, the ribs 130, 131 are configured such that the upperends of the ribs 130, 131 lie in a common plane to support the filter33, and the lower ends of the ribs are in contact with the wall 112.

In the illustrated example, the wall 112 has a slight curvature andportions of the wall 112 are generally inclined toward the suction motorair inlet 113. In this configuration, the height 133 at the outer end ofthe ribs 131 (disposed away from the air inlet 113) is less than theheight 113 at the inner ends of the ribs 131 (the ends adjacent thesuction motor inlet 113). Providing constant contact between the loweredges of the ribs 131 and the wall 112 may help impart rotation to theair flow and may help prevent air from flowing underneath the ribs 131.

Also referring to FIG. 61, the suction motor housing 12 optionallyincludes a shroud 135 surrounding the suction motor 8. The shroud 135 isconfigured to protect and optionally support the suction motor 8, andmay also function as a finger guard to prevent a user from accidentlycontacting the suction motor 8 when the door 13 is open or removed. Theshroud 135 also includes a plurality of air flow apertures 136 to allowair exiting the suction motor 8 to flow through the to the clean airoutlet 6.

Suction Motor Housing Construction

The following is a description of a suction motor construction that maybe used by itself in any surface cleaning apparatus or in anycombination or sub-combination with any other feature or featuresdisclosed herein.

Optionally, portions of the shroud 135 and/or motor housing 12 may beconfigured to help reduce the amount of suction motor noise that escapesthe housing 12. This may help reduce the overall amount of noiseproduced by the surface cleaning apparatus 1. Alternatively, or inaddition, to reducing the noise output, the shroud 135 and housing 12may be configured to help tune the noise generated and to filter outparticular noise frequencies.

Referring to FIG. 63, a schematic cross-sectional representation ofanother embodiment of a suction motor shroud 16135 is illustrated. Thesuction motor shroud 16135 is analogous to shroud 135, and analogousfeatures may be identified using like reference characters indexed by16,000. In this embodiment, the housing 16012 includes a sidewall 16137surrounding the suction motor 16008 and a bottom wall 138. The suctionmotor 16008 is mounted to a collar 16139 that is suspended within thehousing 16012 via ribs 16140.

In this configuration, air enters the suction motor 16008 via its airinlet 16113 and exits via the motor outlet 16141, which is in the radialdirection in the illustrated example. From the air outlet 16141, the airis directed downwardly and flows toward the bottom wall 16138. In theillustrated embodiment, the bottom wall 16138 is curved or scalloped tohelp smoothly redirect the airflow upwards, towards the air outlet 16136(which in this example is a generally annular gap between the wall 13137and collar 16139). Providing curved surfaces on the bottom wall 16138may help reduce turbulence in the airflow and may help reduce the noiseescaping the suction motor housing by directing some of the noiseinwardly. The radius 16142 of the curved portions of the wall 16138 maybe any suitable radius. Upstanding projection 16142 extends upwardlyfrom the bottom wall 16138 and helps form the curved portions of thebottom wall 16138 into a generally torus-like configuration, instead offorming a single continuous bowl-like surface covering the entire lowerend of the shroud 16135. This may help prevent air from flowing acrossthe centerline of the shroud 16135, which may help prevent mixing orother turbulent behavior.

Referring to FIG. 64, another embodiment of a motor shroud 17135 isshown. Shroud 17135 is generally similarly to shroud 135 and analogousfeatures are indicated using like reference characters indexed by 17000.In this embodiment the upper end of the shroud 17135 is closed andsupports the upper end of the motor 17008. The bottom end of the shroud17135 includes a bottom wall 17138 that is curved. As air exits the airoutlet 17141 of the suction motor 17008 it can flow downwardly withinthe shroud 17135 and may be re-directed smoothly by the rounded wall17138, and then ejected via the air apertures 17136. Providing a smoothtransition surface on bottom wall 17138 to re-direct and guide the airflow may help reduce the turbulence and may help smooth the air flow.This may help reduce noise generated by the surface cleaning apparatus.An upstanding projection 17142 projects inwardly from the bottom wall17138 and helps shape the bottom of the shroud 17135 into a generallytorus-shaped configuration as opposed to a generally bowl-like shape.Providing projection 17142 may help prevent air from flowing across thecenter of the shroud 17135 (i.e. from left to right as illustrated, orvice versa) which may help limit mixing or other turbulence inducingflows.

Referring to FIG. 65, another embodiment of a motor shroud 18135 isshown. Shroud 18135 is generally similarly to shroud 135 and analogousfeatures are indicated using like reference characters indexed by 18000.Alternatively, or in addition, to providing rounded features on the endwall or bottom surface of the shroud 18135, the shroud 18135 may also beconfigured to include scalloped or rounded portions in the sidewall ofthe shroud 18137. FIG. 65 is a top view of section motor 18008positioned within the shroud 18135 and the motor 18008 is configured toreceive air via air inlet 18113 and to eject air radially via outlet18141. In the illustrated example, radial air outlet 18141 is directedin one direction, to the right as illustrated, such that air exiting themotor will tend to be directed to the right side of the shroud 18135 asillustrated. In this configuration, portions of the sidewall 18137 thatare facing the air outlet 18141 may be curved to help guide and directair exiting the outlet 18141 and directed inwardly and, optionally, toan opposing side of the shroud 18135 that comprises the air apertures18136. Optionally, a projection 18142 can extend inwardly from thesidewall 18137 to divide the interior of the shroud 18135 into twoportions and to prevent airflow at the outlet 18141 from mixing.Providing the air outlet 18141 directly opposite (i.e., 180° apart from)the air apertures 18136 may help extend the amount of time it takes forair exiting the motor to reach the apertures 18136 which may increasethe likelihood that air exiting the outlets 18136 will be smooth orlaminar which may help reduce noise output. Alternatively, instead ofthe configuration illustrated, the air outlet has a motor 18141 may bepositioned at any relative orientation to the air outlets 18136including for example 90° to the outlets 18136 or directly opposite theoutlets 18136.

Motor Shroud

The following is a description of a suction motor shroud that may beused by itself in any surface cleaning apparatus or in any combinationor sub-combination with any other feature or features disclosed herein.

Referring to FIG. 66, an alternate embodiment of a motor shroud 19135 isshown. Shroud 19135 is generally similar to motor shroud 135 inanalogous features will be identified using like reference charactersindexed by 19000's. In this embodiment, instead of comprising a singlelayer, the motor shroud 19135 includes four concentric sub-shrouds19145, 19146, 19147 and 19148. Each sub-shroud 19145, 19146, 19147 and19148 is positioned to generally surround the motor 19008 and to nestamongst the other sub-shrouds. Referring also to FIG. 67, in thisconfiguration air flowing radially from the suction motor outlets 19141will sequentially pass through each sub-shroud 19148, 19147, 19146,19145 before reaching the outer most air apertures 19136.

Optionally, each sub-shroud can be provided with air openings orapertures of a different configuration. For example, apertures in thesub-shrouds may be of different sizes, different shapes and may be indifferent positions relative to each other. Providing apertures oropenings of different sizes and/or configurations may help limit overallnoise output as each opening may be relatively more effective atscreening noise at a given frequency and therefore stacking the openingsin sequence may help sequentially filter out a variety of differentfrequencies.

In the illustrated example, the outer most sub-shroud 19145 may form theoverall outer wall 19137 of the shroud 19135 and includes generallyrectangular apertures 19136. The next sub-shroud 19146 includes aplurality of generally circular air apertures 19149. The apertures 19149can be sized so that they have a different cross-sectional area thanrectangular apertures 19136 and can be positioned such that they aregenerally radially aligned with or alternatively generally radiallyoffset from apertures 19136 in the outer wall 19137. The next shroud19147 includes a plurality of generally smaller, triangular shapedapertures 19150 and the inner most shroud 19148 contains a plurality ofeven smaller circular apertures 19151. The number of apertures formed onany given shroud and their configuration, shape and/or surface area maybe varied and may be selected to help filter out given frequenciesgenerated by suction motor 19008 and air flow flowing through the shroud19135. While the illustrated with an open top, the shroud 19135 may havean upper cover or upper wall that is solid to seal the upper ends of allof the shrouds and to help direct air to flow radially outwardly throughthe apertures.

Sound Absorbing Material

The following is a description of a sound absorbing material that may beused by itself in any surface cleaning apparatus or in any combinationor sub-combination with any other feature or features disclosed herein.

Optionally, portions of the surface cleaning apparatus 1 can be formedfrom or covered/lined with a sound absorbing or sound dampeningmaterial. The material may include a plurality of regions of differentdensity. Portions of the material at a given density may tend toresonate at a given natural frequency, and the densities of the regionsin the material may be selected so that the regions will resonate, ornot resonate, at frequencies that are likely to be produced by thesuction motor 8 and air flowing through the housing 12. Providingdifferent regions with different densities, each having their ownnatural frequency, may allow the sound absorbing material to counter actnoises at a variety of different frequencies. This may be advantageouswhen compared to a generally homogenous material that may tend to have asingle natural frequency. Accordingly, a sheet of sound absorbingmaterial may be constructed from portions of different sound absorbingmaterials that are adhered together to some a continuous self-supportingsheet.

For example, the sound absorbing material may include a plurality ofpieces of different sound absorbing material or nodes held within asurrounding matrix. The plurality of nodes may include variety ofdifferent nodes having different shapes, sizes and/or densities.Optionally, the nodes may be made from the same material as each other,or some of the nodes may be made from a different material. Similarly,some or all of the nodes may be formed from the same material as thesurrounding matrix, or alternatively the matrix may be formed from adifferent material than the nodes.

Each of the nodes and surrounding matrix may be formed from any suitablematerial, including, for example, one or more of polyurethane,polypropylene, polyethylene, rubber, ABS plastic, other plastics, glass,metal and composite materials.

Referring to FIG. 68, a schematic representation of a material 155 thatincludes three sets of nodes 156, 157 and 158 held within a surroundingmatrix of material 159 is provided. Each set of nodes 156, 157, 158 hasa different density, and optionally may have a different shape asillustrated. Alternatively, the nodes 156, 157, 158 may have differentshapes and the same density, or different densities and the same shapes.

Optionally, the nodes 156, 157, 158 may be generally randomlydistributed within the matrix 159. Alternatively, the nodes 156, 157,158 may be arranged in pre-determined patterns.

In the illustrated embodiment, each set of nodes 156, 157, 158 may tendto resonate at a different natural frequency due to their varyingdensities and geometries. Excitation of any given set of the nodes 156,157, 158 by sound produced by the surface cleaning apparatus 1 may causethe set of nodes 156, 157, 158 to vibrate. The matrix 159 may absorband/or dissipate some or all of the vibrations, thereby dampening soundwaves at the given frequency, and reducing the amount of sound thatpasses through the material 155.

What has been described above has been intended to be illustrative ofthe invention and non-limiting and it will be understood by personsskilled in the art that other variants and modifications may be madewithout departing from the scope of the invention as defined in theclaims appended hereto. The scope of the claims should not be limited bythe preferred embodiments and examples, but should be given the broadestinterpretation consistent with the description as a whole.

What is claimed is:
 1. A cyclone comprising a cyclone chamber having anair inlet, an air outlet, a screen upstream of the air outlet, alongitudinal axis, a first end wall, a second end wall and a sidewall,the air inlet having a cross sectional area in a plane transverse to adirection of airflow through the air inlet and the screen having aninner end spaced longitudinally inwardly from the air outlet and havinga cross-sectional area transverse to the cyclone axis that is less thanthe cross sectional area of the air inlet.
 2. The cyclone of claim 1wherein the cross sectional area of the inner end of the screen is60-90% the cross sectional area of the air inlet.
 3. The cyclone ofclaim 1 wherein the cross sectional area of the inner end of the screenis 70-80% the cross sectional area of the air inlet.
 4. The cyclone ofclaim 1 wherein the screen is tapered outwardly towards to air outlet.5. The cyclone of claim 1 wherein the screen has an outer end at the airoutlet and the air outlet has a diameter proximate that of the outer endof the screen.
 6. The cyclone of claim 1 wherein the screen has an outerend at the air outlet that is recessed radially inwardly of the airoutlet.
 7. The cyclone of claim 1 wherein the air outlet comprises avortex finder, the air inlet and the vortex finder are provided at thefirst end wall, wherein the vortex finder extends into the cyclonechamber a first distance and the air inlet has an inner end that extendsinto the cyclone chamber a distance less than the first distance.
 8. Thecyclone of claim 1 wherein the air outlet comprises a vortex finder, theair inlet and the vortex finder are provided at the first end wall and aportion of the first end wall extends between the air inlet and thevortex finder and the portion is flat.
 9. The cyclone of claim 1 whereinthe air inlet is provided at a first juncture of the sidewall and thefirst end wall, wherein the first juncture downstream of the air inletis configured to at least approximate a portion of a shape of the airinlet that is adjacent the first juncture.
 10. The cyclone of claim 9wherein the first juncture extends at an angle to the walls betweenwhich it is positioned.
 11. The cyclone of claim 10 wherein at the firstjuncture is rounded.
 12. The cyclone of claim 1 wherein the air outletcomprises a vortex finder having an upstream end and a downstream endand the downstream end is wider than the upstream end.
 13. The cycloneof claim 12 wherein the vortex finder is flared in a downstreamdirection.
 14. A surface cleaning apparatus comprising the cyclone ofclaim 1, an air flow path extending from a dirty air inlet to a cleanair outlet and including a suction motor and the cyclone, a pre-motorfilter having an outer perimeter and positioned in the air flow pathbetween the cyclone and the suction motor and at least one of anupstream air plenum that is positioned upstream of the pre-motor filterand a downstream air plenum that is positioned downstream of thepre-motor filter wherein at least one of the upstream and the downstreamair plenum comprises an end wall spaced from the pre-motor filter andcomprising a first portion having an air flow port and a second portionproximate the outer perimeter of the pre-motor filter, wherein the firstportion and the second portion meet at a first juncture that extends atan angle to the first portion and the second portion.
 15. The surfacecleaning apparatus of claim 14 wherein the first portion extendsgenerally laterally and has an outer end and an inner end proximate theair flow port and the outer end is closer to the pre-motor filter thenthe inner end.
 16. The surface cleaning apparatus of claim 14 whereinthe first juncture is rounded.
 17. The surface cleaning apparatus ofclaim 14 wherein the air outlet comprises a vortex finder, the surfacecleaning apparatus comprises the upstream air plenum and the air flowport comprises an air inlet port that is aligned with the vortex finder.18. The surface cleaning apparatus of claim 17 wherein the vortex finderextends to the air inlet port.
 19. The surface cleaning apparatus ofclaim 18 wherein the vortex finder and the end wall meet at a secondjuncture, wherein the second juncture extends at an angle to both thevortex finder and the end wall.
 20. The surface cleaning apparatus ofclaim 19 wherein the second juncture is rounded.